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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# This file defines static prefs, i.e. those that are defined at startup and
# used entirely or mostly from C++ and/or Rust code.
#
# The file is separated into sections, where each section contains a group of
# prefs that all share the same first segment of their name -- all the "gfx.*"
# prefs are together, all the "network.*" prefs are together, etc. Sections
# must be kept in alphabetical order, but prefs within sections need not be.
#
# Basics
# ------
# Any pref defined in one of the files included here should *not* be defined
# in a data file such as all.js; that would just be useless duplication.
#
# (Except under unusual circumstances where the value defined here must be
# overridden, e.g. for some Thunderbird prefs. In those cases the default
# value from the data file will override the static default value defined
# here.)
#
# Please follow the existing prefs naming convention when considering adding a
# new pref, and don't create a new pref group unless it's appropriate and there
# are likely to be multiple prefs within that group. (If you do, you'll need to
# update the `pref_groups` variable in modules/libpref/moz.build.)
#
# Definitions
# -----------
# A pref definition looks like this:
#
# - name: <pref-name> # mandatory
# type: <cpp-type> # mandatory
# value: <default-value> # mandatory
# mirror: <never | once | always> # mandatory
# do_not_use_directly: <true | false> # optional
# include: <header-file> # optional
# rust: <true | false> # optional
# set_spidermonkey_pref: <false | startup | always> # optional
#
# - `name` is the name of the pref, without double-quotes, as it appears
# in about:config. It is used in most libpref API functions (from both C++
# and JS code).
#
# - `type` is one of `bool`, `int32_t`, `uint32_t`, `float`, an atomic version
# of one of those, `String` or `DataMutexString`. Note that float prefs are
# stored internally as strings. The C++ preprocessor doesn't like template
# syntax in a macro argument, so use the typedefs defined in
# StaticPrefsBase.h; for example, use `RelaxedAtomicBool` instead of
# `Atomic<bool, Relaxed>`.
#
# - `value` is the default value. Its type should be appropriate for
# <cpp-type>, otherwise the generated code will fail to compile. A complex
# C++ numeric expressions like `60 * 60` (which the YAML parser cannot treat
# as an integer or float) is treated as a string and passed through without
# change, which is useful.
#
# - `mirror` indicates how the pref value is mirrored into a C++ variable.
#
# * `never`: There is no C++ mirror variable. The pref value can only be
# accessed via the standard libpref API functions.
#
# * `once`: The pref value is mirrored into a variable at startup; the
# mirror variable is left unchanged after that. (The exact point at which
# all `once` mirror variables are set is when the first `once` mirror
# variable is accessed, via its getter function.) This is mostly useful for
# graphics prefs where we often don't want a new pref value to apply until
# restart. Otherwise, this update policy is best avoided because its
# behaviour can cause confusion and bugs.
#
# * `always`: The mirror variable is always kept in sync with the pref value.
# This is the most common choice.
#
# When a mirror variable is present, a getter will be created that can access
# it. Using the getter function to read the pref's value has the two
# following advantages over the normal API functions.
#
# * A direct variable access is faster than a hash table lookup.
#
# * A mirror variable can be accessed off the main thread. If a pref *is*
# accessed off the main thread, it should have an atomic type. Assertions
# enforce this.
#
# Note that Rust code must access the mirror variable directly, rather than
# via the getter function.
#
# - `do_not_use_directly` indicates if `_DoNotUseDirectly` should be appended to
# the name of the getter function. This is simply a naming convention
# indicating that there is some other wrapper getter function that should be
# used in preference to the normal static pref getter. Defaults to `false` if
# not present. Cannot be used with a `never` mirror value, because there is
# no getter function in that case.
#
# - `include` names a header file that must be included for the pref value to
# compile correctly, e.g. because it refers to a code constant. System
# headers should be surrounded with angle brackets, e.g. `<cmath>`.
#
# - `rust` indicates if the mirror variable is used by Rust code. If so, it
# will be usable via the `static_prefs::pref!` macro, e.g.
# `static_prefs::pref!("layout.css.cross-fade.enabled")`.
#
# - `set_spidermonkey_pref` indicates whether SpiderMonkey boilerplate code
# should be generated for this pref. If this is set to 'startup', the
# pref on the SpiderMonkey side is only set during process startup. If set to
# 'always', the SpiderMonkey pref value is also updated when this pref is
# changed at runtime.
# This option is only valid for javascript.options.* prefs.
#
# The getter function's base name is the same as the pref's name, but with
# '.' or '-' chars converted to '_', to make a valid identifier. For example,
# the getter for `foo.bar_baz` is `foo_bar_baz()`. This is ugly but clear,
# and you can search for both the pref name and the getter using the regexp
# /foo.bar.baz/. Suffixes are added as follows:
#
# - If the `mirror` value is `once`, `_AtStartup` is appended, to indicate the
# value was obtained at startup.
#
# - If the `do_not_use_directly` value is true, `_DoNotUseDirectly` is
# appended.
#
# Preprocessor
# ------------
# Note finally that this file is preprocessed by preprocessor.py, not the C++
# preprocessor. As a result, the following things may be surprising.
#
# - YAML comments start with a '#', so putting a comment on the same line as a
# preprocessor directive is dubious. E.g. avoid lines like `#define X 3 #
# three` because the ` # three` will be part of `X`.
#
# - '@' use is required for substitutions to occur. E.g. with `#define FOO 1`,
# `FOO` won't be replaced with `1` unless it has '@' chars around it.
#
# - Spaces aren't permitted between the leading '#' and the name of a
# directive, e.g. `#ifdef XYZ` works but `# ifdef XYZ` does not.
#
# Please indent all prefs defined within #ifdef/#ifndef conditions. This
# improves readability, particular for conditional blocks that exceed a single
# screen. But note that the leading '-' in a definition must remain in the
# first column for it to be valid YAML.
#ifdef RELEASE_OR_BETA
#define IS_NOT_RELEASE_OR_BETA false
#else
#define IS_NOT_RELEASE_OR_BETA true
#endif
#ifdef NIGHTLY_BUILD
#define IS_NIGHTLY_BUILD true
#define IS_NOT_NIGHTLY_BUILD false
#else
#define IS_NIGHTLY_BUILD false
#define IS_NOT_NIGHTLY_BUILD true
#endif
#if defined(NIGHTLY_BUILD) || defined(MOZ_DEV_EDITION)
#define IS_NIGHTLY_OR_DEV_EDITION true
#else
#define IS_NIGHTLY_OR_DEV_EDITION false
#endif
#ifdef MOZILLA_OFFICIAL
#define IS_NOT_MOZILLA_OFFICIAL false
#else
#define IS_NOT_MOZILLA_OFFICIAL true
#endif
#ifdef EARLY_BETA_OR_EARLIER
#define IS_EARLY_BETA_OR_EARLIER true
#define IS_NOT_EARLY_BETA_OR_EARLIER false
#else
#define IS_EARLY_BETA_OR_EARLIER false
#define IS_NOT_EARLY_BETA_OR_EARLIER true
#endif
#if defined(MOZ_DEV_EDITION) || defined(EARLY_BETA_OR_EARLIER)
#define IS_DEV_EDITION_OR_EARLY_BETA_OR_EARLIER true
#else
#define IS_DEV_EDITION_OR_EARLY_BETA_OR_EARLIER false
#endif
#ifdef ANDROID
#define IS_ANDROID true
#define IS_NOT_ANDROID false
#else
#define IS_ANDROID false
#define IS_NOT_ANDROID true
#endif
#ifdef XP_WIN
#define IS_XP_WIN true
#define IS_NOT_XP_WIN false
#else
#define IS_XP_WIN false
#define IS_NOT_XP_WIN true
#endif
#ifdef XP_MACOSX
#define IS_XP_MACOSX true
#define IS_NOT_XP_MACOSX false
#else
#define IS_XP_MACOSX false
#define IS_NOT_XP_MACOSX true
#endif
#ifdef XP_IOS
#define IS_IOS true
#define IS_NOT_IOS false
#else
#define IS_IOS false
#define IS_NOT_IOS true
#endif
#if defined(ANDROID) || defined(XP_IOS)
#define IS_MOBILE true
#define IS_NOT_MOBILE false
#else
#define IS_MOBILE false
#define IS_NOT_MOBILE true
#endif
#---------------------------------------------------------------------------
# Prefs starting with "accessibility."
#---------------------------------------------------------------------------
# Tab focus model bit field:
# 1 focuses text controls, 2 focuses other form elements, 4 adds links.
# Most users will want 1, 3, or 7. On macOS we expose a checkbox to alter
# between 7 and 3.
- name: accessibility.tabfocus
type: int32_t
value: 7
mirror: always
# Only on mac tabfocus is expected to handle UI widgets as well as web content.
# FIXME(emilio): This is weird now that we have a lot of HTML in our pages.
- name: accessibility.tabfocus_applies_to_xul
type: bool
value: @IS_XP_MACOSX@
mirror: always
- name: accessibility.accesskeycausesactivation
type: bool
value: true
mirror: always
- name: accessibility.monoaudio.enable
type: RelaxedAtomicBool
value: false
mirror: always
- name: accessibility.browsewithcaret
type: RelaxedAtomicBool
value: false
mirror: always
- name: accessibility.AOM.enabled
type: bool
value: false
mirror: always
- name: accessibility.ARIAElementReflection.enabled
type: bool
value: true
mirror: always
# Whether to enable all accessibility cache domains on startup.
# * false: enable domains as needed
# * true: enable all domains regardless of need (cache everything)
- name: accessibility.enable_all_cache_domains
type: bool
value: false
mirror: once
# Whether form controls and images should be focusable with mouse, in content
# documents.
#
# This matches historical macOS / Safari behavior.
#
# * 0: never
# * 1: always
# * 2: on content documents
- name: accessibility.mouse_focuses_formcontrol
type: int32_t
#ifdef XP_MACOSX
value: 2
#else
value: 1
#endif
mirror: always
# Whether to enable support for the UI Automation API on Windows. Values:
# * 0: Never.
# * 1: Always.
# * 2: Enable unless incompatible accessibility clients are detected.
- name: accessibility.uia.enable
type: uint32_t
value: 0
mirror: always
do_not_use_directly: true
# Whether to avoid accessibility activation on Windows shortly after clipboard
# copy.
#
# Possible values are:
# * 0: never
# * 1: always
# * 2 (or others): when needed
- name: accessibility.windows.suppress-after-clipboard-copy
type: uint32_t
value: 2
mirror: always
# Whether to avoid accessibility activation on Windows shortly after max button
# hit-test for the "snap layout" feature.
#
# Possible values are:
# * 0: never
# * 1: always
# * 2 (or others): when needed
- name: accessibility.windows.suppress-for-snap-layout
type: uint32_t
value: 2
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "alerts."
#---------------------------------------------------------------------------
# Whether to use platform-specific backends for showing desktop notifications.
# If no such backend is available, or if the pref is false, then XUL
# notifications are used.
- name: alerts.useSystemBackend
type: bool
value: true
mirror: always
#if defined(XP_WIN)
# On Windows, a COM Surrogate notification server receives notification events
# and can relaunch the application after it has been closed.
- name: alerts.useSystemBackend.windows.notificationserver.enabled
type: bool
value: true
mirror: never
#endif
#ifdef ANDROID
#---------------------------------------------------------------------------
# Prefs starting with "android."
#---------------------------------------------------------------------------
# On Android, we want an opaque background to be visible under the page,
# so layout should not force a default background.
- name: android.widget_paints_background
type: RelaxedAtomicBool
value: true
mirror: always
- name: android.touch_resampling.enabled
type: RelaxedAtomicBool
value: false
mirror: always
#endif
#---------------------------------------------------------------------------
# Prefs starting with "apz."
# The apz prefs are explained in AsyncPanZoomController.cpp
#---------------------------------------------------------------------------
# amount we zoom in for a double tap gesture if we couldn't find any content
# based rect to zoom to
- name: apz.doubletapzoom.defaultzoomin
type: AtomicFloat
value: 1.2f
mirror: always
- name: apz.scrollbarbuttonrepeat.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# After a user has executed a pan gesture, we may receive momentum phase pan
# gestures from the OS. This specifies how long we should wait following the
# pan end gesture for possible momentum phase pan gestures before sending the
# TransformEnd notification.
- name: apz.scrollend-event.content.delay_ms
type: RelaxedAtomicInt32
value: 100
mirror: always
- name: apz.wr.activate_all_scroll_frames
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.wr.activate_all_scroll_frames_when_fission
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.prefer_jank_minimal_displayports
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.allow_double_tap_zooming
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.mac.enable_double_tap_zoom_touchpad_gesture
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.allow_immediate_handoff
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.allow_zooming
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.max_zoom
type: AtomicFloat
value: 10.0f
mirror: always
- name: apz.min_zoom
type: AtomicFloat
value: 0.25f
mirror: always
- name: apz.allow_zooming_out
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.android.chrome_fling_physics.friction
type: AtomicFloat
value: 0.015f
mirror: always
- name: apz.android.chrome_fling_physics.inflexion
type: AtomicFloat
value: 0.35f
mirror: always
- name: apz.android.chrome_fling_physics.stop_threshold
type: AtomicFloat
value: 0.1f
mirror: always
- name: apz.autoscroll.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.axis_lock.breakout_angle
type: AtomicFloat
value: float(M_PI / 8.0) # 22.5 degrees
mirror: always
include: <cmath>
- name: apz.axis_lock.breakout_threshold
type: AtomicFloat
value: 1.0f / 32.0f
mirror: always
- name: apz.axis_lock.direct_pan_angle
type: AtomicFloat
value: float(M_PI / 3.0) # 60 degrees
mirror: always
include: <cmath>
- name: apz.axis_lock.lock_angle
type: AtomicFloat
value: float(M_PI / 6.0) # 30 degrees
mirror: always
include: <cmath>
# Whether to lock touch scrolling to one axis at a time. When a new
# axis lock mode is added, the APZCAxisLockCompatTester GTest shoud
# be updated to include the lock mode value.
# 0 = FREE (No locking at all)
# 1 = STANDARD (Once locked, remain locked until scrolling ends)
# 2 = STICKY (Allow lock to be broken, with hysteresis)
# 3 = DOMINANT_AXIS (Only allow movement on one axis at a time, only
# applies to touchpad scrolling)
- name: apz.axis_lock.mode
type: RelaxedAtomicInt32
#if defined(XP_MACOSX)
value: 3
#else
value: 2
#endif
mirror: always
- name: apz.content_response_timeout
type: RelaxedAtomicInt32
value: 400
mirror: always
- name: apz.danger_zone_x
type: RelaxedAtomicInt32
value: 50
mirror: always
- name: apz.danger_zone_y
type: RelaxedAtomicInt32
value: 100
mirror: always
- name: apz.disable_for_scroll_linked_effects
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.displayport_expiry_ms
type: RelaxedAtomicUint32
value: 15000
mirror: always
- name: apz.drag.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.drag.touch.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.enlarge_displayport_when_clipped
type: RelaxedAtomicBool
value: @IS_ANDROID@
mirror: always
# Test only.
- name: apz.fixed-margin-override.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Test only.
- name: apz.fixed-margin-override.bottom
type: RelaxedAtomicInt32
value: 0
mirror: always
# Test only.
- name: apz.fixed-margin-override.top
type: RelaxedAtomicInt32
value: 0
mirror: always
- name: apz.fling_accel_base_mult
type: AtomicFloat
value: 1.0f
mirror: always
- name: apz.fling_accel_supplemental_mult
type: AtomicFloat
value: 1.0f
mirror: always
- name: apz.fling_accel_min_fling_velocity
type: AtomicFloat
value: 1.5f
mirror: always
- name: apz.fling_accel_min_pan_velocity
type: AtomicFloat
value: 0.8f
mirror: always
- name: apz.fling_accel_max_pause_interval_ms
type: RelaxedAtomicInt32
value: 50
mirror: always
- name: apz.fling_curve_function_x1
type: float
value: 0.0f
mirror: once
- name: apz.fling_curve_function_x2
type: float
value: 1.0f
mirror: once
- name: apz.fling_curve_function_y1
type: float
value: 0.0f
mirror: once
- name: apz.fling_curve_function_y2
type: float
value: 1.0f
mirror: once
- name: apz.fling_curve_threshold_inches_per_ms
type: AtomicFloat
value: -1.0f
mirror: always
- name: apz.fling_friction
type: AtomicFloat
value: 0.002f
mirror: always
- name: apz.fling_min_velocity_threshold
type: AtomicFloat
value: 0.5f
mirror: always
- name: apz.fling_stop_on_tap_threshold
type: AtomicFloat
value: 0.05f
mirror: always
- name: apz.fling_stopped_threshold
type: AtomicFloat
value: 0.01f
mirror: always
- name: apz.touch_acceleration_factor_x
type: float
value: 1.0f
mirror: always
- name: apz.touch_acceleration_factor_y
type: float
value: 1.0f
mirror: always
#ifdef MOZ_WIDGET_GTK
- name: apz.gtk.kinetic_scroll.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.gtk.pangesture.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Mode to use when receiving pan gesture input.
#
# * 0: Auto mode (uses the default behavior, subject to change).
# * 1: Page mode: Uses gtk deltas as a percentage of the page size to scroll. This mode matches:
#
#
# * 2: Pixel mode: Uses gtk deltas as a fixed pixel multiplier. This mode matches e.g. GNOME web.
#
# (multiplied then by pixelsPerLineStep which in GNOME-web is 40).
- name: apz.gtk.pangesture.delta_mode
type: uint32_t
value: 0
mirror: always
- name: apz.gtk.pangesture.page_delta_mode_multiplier
type: float
value: 1.0f
mirror: always
- name: apz.gtk.pangesture.pixel_delta_mode_multiplier
type: float
value: 40.0f
mirror: always
- name: apz.gtk.touchpad_pinch.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.gtk.touchpad_pinch.three_fingers.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.gtk.touchpad_hold.enabled
type: RelaxedAtomicBool
value: true
mirror: always
#endif
- name: apz.keyboard.enabled
type: bool
value: @IS_NOT_MOBILE@
mirror: once
- name: apz.keyboard.passive-listeners
type: RelaxedAtomicBool
value: @IS_NOT_MOBILE@
mirror: always
- name: apz.keyboard.focus-optimization
type: bool
value: false
mirror: always
- name: apz.max_tap_time
type: RelaxedAtomicInt32
value: 300
mirror: always
- name: apz.max_velocity_inches_per_ms
type: AtomicFloat
value: -1.0f
mirror: always
- name: apz.max_velocity_queue_size
type: uint32_t
value: 5
mirror: once
- name: apz.min_skate_speed
type: AtomicFloat
value: 1.0f
mirror: always
- name: apz.minimap.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.mousemove_hittest_optimization.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.one_touch_pinch.enabled
type: RelaxedAtomicBool
value: @IS_ANDROID@
mirror: always
- name: apz.overscroll.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# The "test async scroll offset" (used via reftest-async-scroll
# or nsIDOMWindowUtils.setAsyncScrollOffset()) can be used to
# trigger overscroll. Used for tests only.
- name: apz.overscroll.test_async_scroll_offset.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.overscroll.min_pan_distance_ratio
type: AtomicFloat
value: 1.0f
mirror: always
- name: apz.overscroll.stop_distance_threshold
type: AtomicFloat
value: 5.0f
mirror: always
- name: apz.overscroll.spring_stiffness
type: AtomicFloat
value: 200
mirror: always
- name: apz.overscroll.damping
type: AtomicFloat
value: 1.1
mirror: always
- name: apz.overscroll.max_velocity
type: AtomicFloat
value: 10
mirror: always
- name: apz.paint_skipping.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Fetch displayport updates early from the message queue.
- name: apz.pinch_lock.mode
type: RelaxedAtomicInt32
value: 2
mirror: always
- name: apz.pinch_lock.scroll_lock_threshold
type: AtomicFloat
value: 1.0f / 16.0f # 1/16 inches
mirror: always
- name: apz.pinch_lock.span_breakout_threshold
type: AtomicFloat
value: 1.0f / 32.0f # 1/32 inches
mirror: always
- name: apz.pinch_lock.span_lock_threshold
type: AtomicFloat
value: 1.0f / 32.0f # 1/32 inches
mirror: always
- name: apz.pinch_lock.buffer_max_age
type: int32_t
value: 80 # milliseconds
mirror: once
- name: apz.popups.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.popups_without_remote.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Whether to print the APZC tree for debugging.
- name: apz.printtree
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.record_checkerboarding
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
- name: apz.second_tap_tolerance
type: AtomicFloat
value: 0.5f
mirror: always
# If this is true, APZ fully recalculates the scroll thumb size and
# position in the compositor. This leads to the size and position
# being more accurate in scenarios such as async zooming.
- name: apz.scrollthumb.recalc
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.test.fails_with_native_injection
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.test.logging_enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.touch_move_tolerance
type: AtomicFloat
value: 0.1f
mirror: always
- name: apz.touch_scroll.buffer_max_age
type: int32_t
value: 200 # milliseconds
mirror: once
- name: apz.touch_start_tolerance
type: AtomicFloat
value: 0.1f
mirror: always
- name: apz.velocity_bias
type: AtomicFloat
value: 0.0f
mirror: always
- name: apz.velocity_relevance_time_ms
type: RelaxedAtomicUint32
value: 100
mirror: always
- name: apz.windows.force_disable_direct_manipulation
type: RelaxedAtomicBool
value: false
mirror: always
- name: apz.windows.use_direct_manipulation
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.windows.check_for_pan_gesture_conversion
type: RelaxedAtomicBool
value: true
mirror: always
- name: apz.x_skate_highmem_adjust
type: AtomicFloat
value: 0.0f
mirror: always
- name: apz.x_skate_size_multiplier
type: AtomicFloat
value: 1.25f
mirror: always
- name: apz.x_stationary_size_multiplier
type: AtomicFloat
value: 1.5f
mirror: always
- name: apz.y_skate_highmem_adjust
type: AtomicFloat
value: 0.0f
mirror: always
- name: apz.y_skate_size_multiplier
type: AtomicFloat
#if defined(MOZ_WIDGET_ANDROID)
value: 1.5f
#else
value: 3.5f
#endif
mirror: always
- name: apz.y_stationary_size_multiplier
type: AtomicFloat
#if defined(MOZ_WIDGET_ANDROID)
value: 1.5f
#else
value: 3.5f
#endif
mirror: always
- name: apz.zoom_animation_duration_ms
type: RelaxedAtomicInt32
#if defined(MOZ_WIDGET_ANDROID)
value: 250
#else
value: 350
#endif
mirror: always
- name: apz.scale_repaint_delay_ms
type: RelaxedAtomicInt32
value: 500
mirror: always
# Whether to use rounded external scroll offsets.
- name: apz.rounded_external_scroll_offset
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "beacon."
#---------------------------------------------------------------------------
# Is support for Navigator.sendBeacon enabled?
- name: beacon.enabled
type: bool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "bidi."
#---------------------------------------------------------------------------
# Whether delete and backspace should immediately delete characters not
# visually adjacent to the caret, or adjust the visual position of the caret
# on the first keypress and delete the character on a second keypress
- name: bidi.edit.delete_immediately
type: bool
value: true
mirror: always
# Bidi caret movement style:
# 0 = logical
# 1 = visual
# 2 = visual, but logical during selection
- name: bidi.edit.caret_movement_style
type: int32_t
#if !defined(XP_LINUX) && defined(NIGHTLY_BUILD)
value: 1
#else
#endif
mirror: always
# Bidi numeral style:
# 0 = nominalnumeralBidi *
# 1 = regularcontextnumeralBidi
# 2 = hindicontextnumeralBidi
# 3 = arabicnumeralBidi
# 4 = hindinumeralBidi
# 5 = persiancontextnumeralBidi
# 6 = persiannumeralBidi
- name: bidi.numeral
type: RelaxedAtomicUint32
value: 0
mirror: always
# Bidi text type
# 1 = charsettexttypeBidi *
# 2 = logicaltexttypeBidi
# 3 = visualtexttypeBidi
- name: bidi.texttype
type: RelaxedAtomicUint32
value: 1
mirror: always
# Bidi direction
# 1 = directionLTRBidi *
# 2 = directionRTLBidi
- name: bidi.direction
type: RelaxedAtomicUint32
value: 1
mirror: always
# Setting this pref to |true| forces Bidi UI menu items and keyboard shortcuts
# to be exposed, and enables the directional caret hook. By default, only
# expose it for bidi-associated system locales.
- name: bidi.browser.ui
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "browser."
#---------------------------------------------------------------------------
- name: browser.active_color
type: String
value: "#EE0000"
mirror: never
- name: browser.active_color.dark
type: String
value: "#FF6666"
mirror: never
- name: browser.anchor_color
type: String
value: "#0000EE"
mirror: never
# If you change this, you probably also want to change
# nsXPLookAndFeel::GenericDarkColor for Linktext.
- name: browser.anchor_color.dark
type: String
value: "#8C8CFF"
mirror: never
- name: browser.autofocus
type: bool
value: true
mirror: always
- name: browser.cache.disk.enable
type: RelaxedAtomicBool
value: true
mirror: always
- name: browser.cache.memory.enable
type: RelaxedAtomicBool
value: true
mirror: always
# Limit of recent metadata we keep in memory for faster access, in KB.
- name: browser.cache.disk.metadata_memory_limit
type: RelaxedAtomicUint32
value: 1024 # 1 MB
mirror: always
# Does the user want smart-sizing?
- name: browser.cache.disk.smart_size.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Disk cache capacity in kilobytes. It's used only when
# browser.cache.disk.smart_size.enabled == false
- name: browser.cache.disk.capacity
type: RelaxedAtomicUint32
value: 256000
mirror: always
# -1 = determine dynamically, 0 = none, n = memory capacity in kilobytes.
- name: browser.cache.memory.capacity
type: RelaxedAtomicInt32
value: -1
mirror: always
# When smartsizing is disabled we could potentially fill all disk space by
# cache data when the disk capacity is not set correctly. To avoid that we
# check the free space every time we write some data to the cache. The free
# space is checked against two limits. Once the soft limit is reached we start
# evicting the least useful entries, when we reach the hard limit writing to
# the entry fails.
- name: browser.cache.disk.free_space_soft_limit
type: RelaxedAtomicUint32
value: 5 * 1024 # 5MB
mirror: always
- name: browser.cache.disk.free_space_hard_limit
type: RelaxedAtomicUint32
value: 1024 # 1MB
mirror: always
# The number of chunks we preload ahead of read. One chunk currently has
# 256kB.
- name: browser.cache.disk.preload_chunk_count
type: RelaxedAtomicUint32
value: 4 # 1 MB of read ahead
mirror: always
# Max-size (in KB) for entries in disk cache. Set to -1 for no limit.
# (Note: entries bigger than 1/8 of disk-cache are never cached)
- name: browser.cache.disk.max_entry_size
type: RelaxedAtomicUint32
value: 50 * 1024 # 50 MB
mirror: always
# Max-size (in KB) for entries in memory cache. Set to -1 for no limit.
# (Note: entries bigger than than 90% of the mem-cache are never cached.)
- name: browser.cache.memory.max_entry_size
type: RelaxedAtomicInt32
value: 5 * 1024
mirror: always
# Memory limit (in kB) for new cache data not yet written to disk. Writes to
# the cache are buffered and written to disk on background with low priority.
# With a slow persistent storage these buffers may grow when data is coming
# fast from the network. When the amount of unwritten data is exceeded, new
# writes will simply fail. We have two buckets, one for important data
# (priority) like html, css, fonts and js, and one for other data like images,
# video, etc.
# Note: 0 means no limit.
- name: browser.cache.disk.max_chunks_memory_usage
type: RelaxedAtomicUint32
value: 40 * 1024
mirror: always
- name: browser.cache.disk.max_priority_chunks_memory_usage
type: RelaxedAtomicUint32
value: 40 * 1024
mirror: always
# Number of seconds the cache spends writing pending data and closing files
# after shutdown has been signalled. Past that time data is not written and
# files are left open for the OS to clean up.
- name: browser.cache.max_shutdown_io_lag
type: RelaxedAtomicUint32
value: 2
mirror: always
# After the max_shutdown_io_lag has passed, we will attempt to cancel
# blocking IO (on windows). The CacheIOThread may pick up more blocking
# tasks so we want to cancel those too. The main thread will be woken
# up every shutdown_io_time_between_cancellations_ms to cancel the IO
# on the other thread.
- name: browser.cache.shutdown_io_time_between_cancellations_ms
type: RelaxedAtomicUint32
value: 5
mirror: always
# A percentage limit for media content type in the disk cache. When some entries
# need to be evicted and media is over the limit, it's evicted first.
- name: browser.cache.disk.content_type_media_limit
type: RelaxedAtomicInt32
value: 50
mirror: always
# How often to validate document in cache
# 0 = once-per-session,
# 1 = each-time,
# 2 = never,
# 3 = when-appropriate/automatically
- name: browser.cache.check_doc_frequency
type: RelaxedAtomicUint32
value: 3
mirror: always
# Compression level for cached JavaScript bytecode
# 0 = do not compress,
# 1 = minimal compression,
# 9 = maximal compression
- name: browser.cache.jsbc_compression_level
type: RelaxedAtomicUint32
value: 0
mirror: always
# Whether tooltips are enabled.
- name: browser.chrome.toolbar_tips
type: bool
value: true
mirror: always
# Whether tooltips are hidden on keydown.
# 0: never
# 1: always
# 2: only on non-modifier keys
- name: browser.chrome.toolbar_tips.hide_on_keydown
type: uint32_t
#if defined(XP_WIN)
value: 0
#else
value: 2
#endif
mirror: always
# DLP agent name, for display in the browser
- name: browser.contentanalysis.agent_name
type: String
value: "A DLP agent"
mirror: never
# (optional) The organization name that the DLP agent should have. If this is
# non-empty and the DLP agent is not signed with this organization name,
# Firefox will fail the connection.
- name: browser.contentanalysis.client_signature
type: String
value: ""
mirror: never
# Content analysis by external applications, e.g. data-loss prevention apps
- name: browser.contentanalysis.enabled
type: bool
value: false
mirror: always
# What content analysis should return if there is a problem communicating
# with the agent. (see DefaultResponse enum in ContentAnalysis.h)
# Make sure these stay in sync with the out-of-range check in Policies.sys.mjs.
#
# 0: Block all requests
# 1: Warn on all requests (which lets the user decide)
# 2: Allow all requests
- name: browser.contentanalysis.default_result
type: uint32_t
value: 0
mirror: always
# What content analysis should return if the agent takes too long to respond
# to a request. (see DefaultResponse enum in ContentAnalysis.h)
# Make sure these stay in sync with the out-of-range check in Policies.sys.mjs.
#
# 0: Block all requests
# 1: Warn on all requests (which lets the user decide)
# 2: Allow all requests
- name: browser.contentanalysis.timeout_result
type: uint32_t
value: 0
mirror: always
# Is the IPC pipe to the DLP tool specific to the user or to the system?
- name: browser.contentanalysis.is_per_user
type: bool
value: true
mirror: always
# Path name of pipe used to connect to a configured DLP agent.
- name: browser.contentanalysis.pipe_path_name
type: String
value: "path_user"
mirror: never
# Space-separated list of regexs that are compared to URLs of resources
# being checked by content-analysis. Resources that match are not checked
# and are always permitted.
# By default this does not check any about: page except for about:blank
# and about:srcdoc.
- name: browser.contentanalysis.allow_url_regex_list
type: String
value: "^about:(?!blank|srcdoc).*"
mirror: never
# Space-separated list of regexs that are compared to URLs of resources
# being checked by content-analysis. Resources that match are not checked
# and are always denied.
- name: browser.contentanalysis.deny_url_regex_list
type: String
value: ""
mirror: never
# Should CA ignore the system setting and use silent notifications?
- name: browser.contentanalysis.silent_notifications
type: bool
value: false
mirror: always
# Time (secs) after which content analysis operations are considered timed-out
# A non-positive value indicates a timeout of 25ms, which is used for testing.
- name: browser.contentanalysis.agent_timeout
type: int32_t
value: 300
mirror: always
# Should Firefox show a notification or dialog when content analysis blocks
# access?
- name: browser.contentanalysis.show_blocked_result
type: bool
value: true
mirror: always
# Should Firefox bypass content analysis for pastes and drags whose source
# is the same tab?
- name: browser.contentanalysis.bypass_for_same_tab_operations
type: bool
value: false
mirror: always
# Max number of concurrent connections to the DLP agent. For stability
# reasons, values exceeding 256 will be ignored.
- name: browser.contentanalysis.max_connections
type: uint32_t
value: 32
mirror: always
# Should Firefox use content analysis for clipboard operations?
# Note that this has no effect unless browser.contentanalysis.enabled
# is true.
- name: browser.contentanalysis.interception_point.clipboard.enabled
type: bool
value: true
mirror: always
# Should Firefox only analyze plain text contents of the clipboard?
# If this is false, all formats on the clipboard will be analyzed.
# Note that regardless of this setting, files on the clipboard
# will be analyzed.
- name: browser.contentanalysis.interception_point.clipboard.plain_text_only
type: bool
value: true
mirror: always
# Should Firefox use content analysis for drag and drop operations?
# Note that this has no effect unless browser.contentanalysis.enabled
# is true.
- name: browser.contentanalysis.interception_point.drag_and_drop.enabled
type: bool
value: true
mirror: always
# Should Firefox only analyze plain text contents for drag and drop
# operations?
# If this is false, all formats that are part of the drag and drop
# operation will be analyzed.
# Note that regardless of this setting, files that are dragged and dropped
# will be analyzed.
- name: browser.contentanalysis.interception_point.drag_and_drop.plain_text_only
type: bool
value: true
mirror: always
# Should Firefox use content analysis for file upload operations through
# a file dialog?
# Note that this has no effect unless browser.contentanalysis.enabled
# is true.
- name: browser.contentanalysis.interception_point.file_upload.enabled
type: bool
value: true
mirror: always
# Should Firefox use content analysis for print operations?
# Note that this has no effect unless browser.contentanalysis.enabled
# is true.
- name: browser.contentanalysis.interception_point.print.enabled
type: bool
value: true
mirror: always
# Content blocking for Enhanced Tracking Protection
- name: browser.contentblocking.database.enabled
type: bool
value: false
mirror: always
# How many recent block/unblock actions per origins we remember in the
# Content Blocking log for each top-level window.
- name: browser.contentblocking.originlog.length
type: uint32_t
value: 32
mirror: always
# Whether memorytesting is enabled when crash reporter client is launched
- name: browser.crashReporter.memtest
type: RelaxedAtomicBool
value: true
mirror: always
# Space-separated list of prioritized memory test kinds
- name: browser.crashReporter.memtestKinds
type: DataMutexString
value: ""
mirror: always
# Control whether we enable the feature of crash pull at all
#Â Disabled by default for now until further notice
- name: browser.crashReports.crashPull
type: bool
value: false
mirror: always
# Should we prompt the user to send targetted crash report requested by devs?
- name: browser.crashReports.requestedNeverShowAgain
type: bool
value: false
mirror: always
# Min font device pixel size at which to turn on high quality.
- name: browser.display.auto_quality_min_font_size
type: RelaxedAtomicUint32
value: 20
mirror: always
- name: browser.display.background_color
type: String
value: "#FFFFFF"
mirror: never
- name: browser.display.background_color.dark
type: String
value: "#1C1B22"
mirror: never
# This preference is a bit confusing because we use the opposite
# string value in the colors dialog to indicate to users how FF HCM
# will behave.
# With resect to document colors, these values mean:
# 0 = "default" = always, except in high contrast mode
# 1 = "always"
# 2 = "never"
#
# On windows, we set this to 0, which means FF HCM will mirror OS HCM.
# Everywhere else, we set this to 1, disabling FF HCM.
- name: browser.display.document_color_use
type: RelaxedAtomicUint32
#if defined(XP_WIN)
value: 0
#else
value: 1
#endif
mirror: always
rust: true
# 0 = always native
# 1 = never native
# other = default
- name: browser.display.windows.non_native_menus
type: RelaxedAtomicUint32
value: 2
mirror: always
rust: true
# This pref dictates whether or not backplates and background images
# are to be drawn, when in high-contrast mode:
# false: do not draw backplates or render background images
# true: render background images and draw backplates
# This condition is only considered when high-contrast mode is enabled
# in Firefox, ie. when the user has:
# (1) mUseAccessibilityMode set to true (Widows high-contrast mode is on)
# AND browser.display.document_color_use set to 0
# (only with high-contrast themes) OR
# (2) browser.display.document_color_use set to 2 (always)
- name: browser.display.permit_backplate
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether we should suppress the background-image of the canvas (the root
# frame) if we're in forced colors mode.
#
# This is important because some sites use background-image with a plain color
# and it causes undesirable results in high-contrast mode.
#
- name: browser.display.suppress_canvas_background_image_on_forced_colors
type: bool
value: true
mirror: always
- name: browser.display.foreground_color
type: String
value: "#000000"
mirror: never
- name: browser.display.foreground_color.dark
type: String
value: "#FBFBFE"
mirror: never
# Determines the behavior of OS zoom settings.
#
# 0: doesn't affect rendering at all
# 1: affects full zoom (dpi, effectively).
# 2: affects text zoom.
#
# Default is (1): Historical behavior on Linux, matches other browsers on
# Windows, and generally creates more consistent rendering.
- name: browser.display.os-zoom-behavior
type: RelaxedAtomicInt32
value: 1
mirror: always
rust: true
# Whether focus rings are always shown by default.
#
# This is the initial value of nsWindowRoot::mShowFocusRings, but it can be
# overridden by system preferences.
- name: browser.display.show_focus_rings
type: bool
value: false
mirror: always
# Enable showing image placeholders while image is loading or when image is broken.
- name: browser.display.show_image_placeholders
type: bool
value: true
mirror: always
# Whether we should always enable focus rings after focus was moved by keyboard.
#
# This behavior matches both historical and GTK / Windows focus behavior.
#
# :focus-visible is intended to provide better heuristics than this.
- name: browser.display.always_show_rings_after_key_focus
type: bool
value: false
mirror: always
# In theory: 0 = never, 1 = quick, 2 = always, though we always just use it as
# a bool!
- name: browser.display.use_document_fonts
type: RelaxedAtomicInt32
value: 1
mirror: always
rust: true
# font-family names for which we'll override use_document_fonts=0, and always
# use the specified font.
# This is to support ligature-icon fonts, which render literal strings like
# "arrow_drop_down" with an icon, even when use_document_fonts is disabled.
# If an author provides & uses such a font, and we decline to use it, we'll end
# up rendering these literal strings where the author intended an icon, which
# can cause all sorts of overlapping/unreadable content.
- name: browser.display.use_document_fonts.icon_font_allowlist
type: String
value: >-
Material Icons,
Material Icons Extended,
Material Icons Outlined,
Material Icons Round,
Material Icons Sharp,
Material Icons Two Tone,
Google Material Icons,
Google Material Icons Filled,
Material Symbols Outlined,
Material Symbols Round,
Material Symbols Rounded,
Material Symbols Sharp,
Google Symbols,
FontAwesome
mirror: never
- name: browser.display.use_system_colors
type: RelaxedAtomicBool
#ifdef XP_WIN
value: true
#else
value: false
#endif
mirror: always
- name: browser.dom.window.dump.enabled
type: RelaxedAtomicBool
value: @IS_NOT_MOZILLA_OFFICIAL@
mirror: always
- name: browser.download.start_downloads_in_tmp_dir
type: bool
value: false
mirror: always
- name: browser.download.always_ask_before_handling_new_types
type: bool
value: false
mirror: always
- name: browser.download.enable_spam_prevention
type: bool
value: false
mirror: always
- name: browser.download.open_pdf_attachments_inline
type: bool
value: false
mirror: always
- name: browser.download.force_save_internally_handled_attachments
type: bool
value: false
mirror: always
- name: browser.download.sanitize_non_media_extensions
type: bool
value: true
mirror: always
# Image document's automatic image sizing.
- name: browser.enable_automatic_image_resizing
type: bool
value: true
mirror: always
# Image document's click-to-resize.
- name: browser.enable_click_image_resizing
type: bool
value: @IS_NOT_MOBILE@
mirror: always
- name: browser.find.ignore_ruby_annotations
type: bool
value: true
mirror: always
#if defined(XP_MACOSX)
# Whether pressing Esc will exit fullscreen.
- name: browser.fullscreen.exit_on_escape
type: bool
value: true
mirror: always
#endif
# The max url length we'll store in history.
#
# The default value is mostly a guess based on various facts:
#
# * IE didn't support urls longer than 2083 chars
# * Sitemaps protocol used to support a maximum of 2048 chars
# * Various SEO guides suggest to not go over 2000 chars
# * Various apps/services are known to have issues over 2000 chars
# * RFC 2616 - HTTP/1.1 suggests being cautious about depending
# on URI lengths above 255 bytes
#
- name: browser.history.maxUrlLength
type: uint32_t
value: 2000
mirror: always
# Max size of push/replaceState data parameter
- name: browser.history.maxStateObjectSize
type: int32_t
value: 16777216
mirror: always
# True to collect wireframes upon navigations / pushState
- name: browser.history.collectWireframes
type: bool
value: false
mirror: always
# If false, show internal error page for HTTP responses with error
# codes (4xx, 5xx) and "Content-Length": 0 instead of blank page
# is disabled on Android.
- name: browser.http.blank_page_with_error_response.enabled
type: bool
#if !defined(ANDROID)
value: false
#else
value: true
#endif
mirror: always
# The minimum area for a rect to be included in a wireframe, in CSS pixels.
#
# The current value of 50 is pretty arbitrary, and will be tuned as we refine
# and test the wireframing capability.
- name: browser.history.wireframeAreaThreshold
type: uint32_t
value: 50
mirror: always
#if defined(XP_WIN) || defined(XP_LINUX)
# Notify TabUnloader or send the memory pressure if the memory resource
# notification is signaled AND the available commit space is lower than
# this value.
- name: browser.low_commit_space_threshold_mb
type: RelaxedAtomicUint32
value: 200
mirror: always
#endif
#ifdef XP_LINUX
# On Linux we also check available memory in comparison to total memory,
# and use this percent value (out of 100) to determine if we are in a
# low memory scenario.
- name: browser.low_commit_space_threshold_percent
type: RelaxedAtomicUint32
value: 5
mirror: always
#endif
# Render animations and videos as a solid color
- name: browser.measurement.render_anims_and_video_solid
type: RelaxedAtomicBool
value: false
mirror: always
- name: browser.navigation.requireUserInteraction
type: bool
value: true
mirror: always
# Indicates if about:newtab shows content (enabled) or just blank.
- name: browser.newtabpage.enabled
type: bool
value: true
mirror: always
# Open PDFs in Edge with the --app flag if it is the default.
- name: browser.pdf.launchDefaultEdgeAsApp
type: bool
value: true
mirror: always
# Maximium delay between keystrokes that will be considered typing (milliseconds).
- name: browser.places.interactions.typing_timeout_ms
type: RelaxedAtomicUint32
value: 3000
mirror: always
# Maximum delay between scroll input events that will be considered a scrolling interaction (milliseconds).
- name: browser.places.interactions.scrolling_timeout_ms
type: RelaxedAtomicUint32
value: 5000
mirror: always
# Number of seconds till the sponsored session is timeout.
- name: browser.places.sponsoredSession.timeoutSecs
type: RelaxedAtomicUint32
value: 3600
mirror: always
# Whether to start the private browsing mode at application startup
- name: browser.privatebrowsing.autostart
type: bool
value: false
mirror: always
# Force usage of in-memory (rather than file on disk) media cache for video streaming when private browsing
- name: browser.privatebrowsing.forceMediaMemoryCache
type: bool
value: false
mirror: always
# Communicates the toolbar color to platform (for e.g., prefers-color-scheme).
#
# Returns whether the toolbar is dark (0), light (1), or system (2). The
# theming code overrides it if appropriate.
- name: browser.theme.toolbar-theme
type: RelaxedAtomicUint32
value: 2
mirror: always
# Communicates the preferred content theme color to platform (for e.g.,
# prefers-color-scheme).
#
# dark (0), light (1), system (2), or toolbar (3).
#
# Default to "toolbar", the theming code sets it appropriately.
- name: browser.theme.content-theme
type: RelaxedAtomicUint32
value: 2
mirror: always
rust: true
# Whether the firefox titlebar respects the
# -moz-windows-accent-color-in-titlebar setting on the tab strip.
- name: browser.theme.windows.accent-color-in-tabs.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Blocked plugin content
- name: browser.safebrowsing.blockedURIs.enabled
type: bool
value: true
mirror: always
# Malware protection
- name: browser.safebrowsing.malware.enabled
type: bool
value: true
mirror: always
# Phishing protection
- name: browser.safebrowsing.phishing.enabled
type: bool
value: true
mirror: always
# Maximum size for an array to store the safebrowsing prefixset.
- name: browser.safebrowsing.prefixset_max_array_size
type: RelaxedAtomicUint32
value: 512*1024
mirror: always
# Whether to only classify top-level channels for safe browsing.
- name: browser.safebrowsing.only_top_level
type: bool
value: true
mirror: always
# SessionStore prefs
# Maximum number of bytes of DOMSessionStorage data we collect per origin.
- name: browser.sessionstore.dom_storage_limit
type: uint32_t
value: 2048
mirror: always
# Maximum number of characters of form field data per field we collect.
- name: browser.sessionstore.dom_form_limit
type: uint32_t
value: 1024*1024*2
mirror: always
# Maximum number of characters of form data we collect per origin.
- name: browser.sessionstore.dom_form_max_limit
type: uint32_t
value: 1024*1024*50
mirror: always
# Minimal interval between two save operations in milliseconds (while the user is active).
- name: browser.sessionstore.interval
type: RelaxedAtomicUint32
value: 15000
mirror: always
# Disable collection of data for session store using the native collector code,
# instead use the older implementation that's not compatible with session
# history in the parent (and thus Fission).
- name: browser.sessionstore.disable_platform_collection
type: bool
#if defined(MOZ_THUNDERBIRD)
value: true
#else
value: false
#endif
mirror: once
do_not_use_directly: true
#if defined(NIGHTLY_BUILD) || defined(MOZ_DEV_EDITION) || defined(DEBUG)
- name: browser.startup.record
type: bool
value: false
mirror: always
#endif
# Causes SessionStore to ignore non-final update messages from
# browser tabs that were not caused by a flush from the parent.
# This is a testing flag and should not be used by end-users.
- name: browser.sessionstore.debug.no_auto_updates
type: RelaxedAtomicBool
value: false
mirror: always
# If set, when a link is opened to a new tab, do not switch to the new tab.
#
# This pref is used when the link is opened with "Open Link in New Tab",
# middle-click, etc.
#
# See also browser.tabs.loadDivertedInBackground, which is used when the website
# diverts the link into a new tab.
- name: browser.tabs.loadInBackground
type: bool
value: true
mirror: always
# Whether we should draw the tabs on top of the titlebar.
#
# no (0), yes (1), or default (2), which is true everywhere except Linux.
- name: browser.tabs.inTitlebar
type: int32_t
value: 2
mirror: always
# If set, use DocumentChannel to directly initiate loads entirely
# from parent-process BrowsingContexts
- name: browser.tabs.documentchannel.parent-controlled
type: bool
value: false
mirror: always
# If set, middle clicking on a link opens the link in a new tab.
- name: browser.tabs.opentabfor.middleclick
type: bool
value: true
mirror: always
# Testing-only pref which makes data: URIs be loaded in a "web" content process
# instead of within a process based on the URI's loader.
- name: browser.tabs.remote.dataUriInDefaultWebProcess
type: bool
value: false
mirror: always
# Testing-only pref to force system-triggered about:blank loads to not change
# content processes. This is used for performance tests which load an
# about:blank document between navigations for historical reasons to avoid
# unnecessary process switches.
- name: browser.tabs.remote.systemTriggeredAboutBlankAnywhere
type: bool
value: false
mirror: always
# Testing-only pref to cause PBrowser creation for a specific BrowsingContext to
# fail, to test the errored codepath.
- name: browser.tabs.remote.testOnly.failPBrowserCreation.enabled
type: bool
value: false
mirror: always
- name: browser.tabs.remote.force-paint
type: bool
value: true
mirror: always
# When this pref is enabled document loads with a mismatched
# Cross-Origin-Embedder-Policy header will fail to load
- name: browser.tabs.remote.useCrossOriginEmbedderPolicy
type: RelaxedAtomicBool
value: true
mirror: always
# This pref makes `credentialless` a valid value for
# Cross-Origin-Embedder-Policy header
- name: browser.tabs.remote.coep.credentialless
type: RelaxedAtomicBool
#if defined(ANDROID)
value: @IS_NIGHTLY_BUILD@
#else
value: true
#endif
mirror: always
do_not_use_directly: true
# When this pref is enabled top level loads with a mismatched
# Cross-Origin-Opener-Policy header will be loaded in a separate process.
- name: browser.tabs.remote.useCrossOriginOpenerPolicy
type: RelaxedAtomicBool
value: true
mirror: always
# When this pref is enabled then we use a separate content process for
# top-level load of file:// URIs
- name: browser.tabs.remote.separateFileUriProcess
type: RelaxedAtomicBool
#if !defined(ANDROID)
value: true
#else
value: false
#endif
mirror: always
# Pref to control whether we use a separate privileged content process
# for certain mozilla webpages (which are listed in the pref
# browser.tabs.remote.separatedMozillaDomains).
- name: browser.tabs.remote.separatePrivilegedMozillaWebContentProcess
type: bool
value: false
mirror: always
# Whether or not process selection for subframes will prefer re-using an
# existing content process over creating a new one. Enabling this pref should
# reduce the number of processes allocated for non-first-party domains if
# dom.ipc.processCount.webIsolated > 1.
- name: browser.tabs.remote.subframesPreferUsed
type: bool
value: true
mirror: always
# When this pref is enabled, opaque response is only allowed to enter the
# content process if it's a response for media (audio, image, video), CSS, or
# JavaScript.
- name: browser.opaqueResponseBlocking
type: RelaxedAtomicBool
#if defined(ANDROID)
value: false
#else
value: true
#endif
mirror: always
# When this pref is enabled, the JS validator will be enabled for
# ORB.
- name: browser.opaqueResponseBlocking.javascriptValidator
type: bool
value: true
mirror: always
# This pref controls how filtering of opaque responses for calls to `Window.fetch`.
# (and similar) is performed in the parent process. This is intended to make sure
# that data that would be filtered in a content process never actually reaches that
# content process.
# 0) Don't filter in the parent process at all, and let content processes handle
# opaque filtering. Regardless of if ORB is enabled or not. N.B. that if ORB
# is enabled opaque responses will be blocked.
# 1) If ORB is enabled, in the parent process, filter the responses that ORB allows.
# N.B. any responses ORB doesn't allow will not send data to a content process
# since they will return a NetworkError. If the request is allowed by ORB, the
# internal response will be intact and sent to the content process as is.
# 2) If ORB is enabled, in the parent process, filter the responses that ORB blocks,
# when they were issued by `Window.fetch` (and similar).
# 3) Filter all responses in the parent, regardless of if ORB is enabled or not.
# This means that opaque responses coming from `Window.fetch` won't even be
# considered for being blocked by ORB.
- name: browser.opaqueResponseBlocking.filterFetchResponse
type: uint32_t
value: 2
mirror: always
do_not_use_directly: true
# This pref controls how exceptions to opaque response blocking for the media MIME types
# `audio/*` and `video/*` are handled. This is because step 8 in the spec that performs
# audio or video type pattern matching cannot handle certain MIME types (yet).
# 0) No exceptions
# 1) Some exceptions, explicitly hard coded in `IsOpaqueSafeListedSpecBreakingMIMEType`
# 2) Allow all MIME types beginning with `audio/*` or `video/*`.
- name: browser.opaqueResponseBlocking.mediaExceptionsStrategy
type: uint32_t
value: 1
mirror: always
do_not_use_directly: true
# When true, zooming will be enabled on all sites, even ones that declare
# user-scalable=no or use touch-action to disable pinch gestures.
- name: browser.ui.zoom.force-user-scalable
type: RelaxedAtomicBool
value: false
mirror: always
- name: browser.viewport.desktopWidth
type: RelaxedAtomicInt32
value: 980
mirror: always
- name: browser.visited_color
type: String
value: "#551A8B"
mirror: never
# If you change this, you probably also want to change
# nsXPLookAndFeel::GenericDarkColor for Visitedtext.
- name: browser.visited_color.dark
type: String
value: "#FFADFF"
mirror: never
# When true, soft reloads (including location.reload())
# will only froce validate the top level document, subresources will
# be loaded normally as-if users normally navigated to the page.
- name: browser.soft_reload.only_force_validate_top_level_document
type: bool
value: true
mirror: always
# Whether or not to save and restore zoom levels on a per-site basis.
- name: browser.zoom.siteSpecific
type: bool
value: @IS_NOT_ANDROID@
mirror: always
# Whether we block opening pickers from background tabs.
- name: browser.disable_pickers_background_tabs
type: RelaxedAtomicBool
value: true
mirror: always
# Whether we block opening pickers from hidden extension pages in WebExtensions.
# This includes background pages and devtools pages, but not background tabs.
- name: browser.disable_pickers_in_hidden_extension_pages
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "channelclassifier."
#---------------------------------------------------------------------------
- name: channelclassifier.allowlist_example
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "clipboard."
#---------------------------------------------------------------------------
# Clipboard behavior.
- name: clipboard.autocopy
type: bool
#if !defined(ANDROID) && !defined(XP_MACOSX) && defined(XP_UNIX)
value: true
#else
value: false
#endif
mirror: always
#ifdef XP_WIN
# allow to copy clipboard data to Clipboard History/Cloud
# (used on sensitive data in about:logins and Private Browsing)
- name: clipboard.copyPrivateDataToClipboardCloudOrHistory
type: bool
value: false
mirror: always
# Whether to put a file promise onto the clipboard when copying images on Windows
- name: clipboard.imageAsFile.enabled
type: bool
value: @IS_NOT_EARLY_BETA_OR_EARLIER@
mirror: always
# On Windows, whether to add PNG before BMP (CF_DIB) in the list of supported
# formats when copying an image to the clipboard.
- name: clipboard.copy_image.as_png
type: RelaxedAtomicBool
value: true
mirror: always
# On Windows, whether we encode an image as PNG (instead of the previous
# default of BMP) when an application to which we are copying an image
# requests that it be provided as a temporary file (CF_HDROP).
- name: clipboard.copy_image_file.as_png
type: RelaxedAtomicBool
value: true
mirror: always
#endif
#---------------------------------------------------------------------------
# Prefs starting with "consoleservice."
#---------------------------------------------------------------------------
#if defined(ANDROID)
# Disable sending console to logcat on release builds.
- name: consoleservice.logcat
type: RelaxedAtomicBool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
#endif
#---------------------------------------------------------------------------
# Prefs starting with "content."
#---------------------------------------------------------------------------
- name: content.cors.disable
type: bool
value: false
mirror: always
# Back off timer notification after count.
# -1 means never.
- name: content.notify.backoffcount
type: int32_t
value: -1
mirror: always
# Notification interval in microseconds.
# The notification interval has a dramatic effect on how long it takes to
# initially display content for slow connections. The current value
# provides good incremental display of content without causing an increase
# in page load time. If this value is set below 1/10 of a second it starts
# to impact page load performance.
- name: content.notify.interval
type: int32_t
value: 120000
mirror: always
# Do we notify based on time?
- name: content.notify.ontimer
type: bool
value: true
mirror: always
# How many times to deflect in interactive mode.
- name: content.sink.interactive_deflect_count
type: int32_t
value: 0
mirror: always
# How many times to deflect in perf mode.
- name: content.sink.perf_deflect_count
type: int32_t
value: 200
mirror: always
# Parse mode for handling pending events.
# 0 = don't check for pending events
# 1 = don't deflect if there are pending events
# 2 = bail if there are pending events
- name: content.sink.pending_event_mode
type: int32_t
#ifdef XP_WIN
value: 1
#else
value: 0
#endif
mirror: always
# How often to probe for pending events. 1 = every token.
- name: content.sink.event_probe_rate
type: int32_t
value: 1
mirror: always
# How long to stay off the event loop in interactive mode (microseconds).
- name: content.sink.interactive_parse_time
type: int32_t
value: 3000
mirror: always
# How long to stay off the event loop in perf mode.
- name: content.sink.perf_parse_time
type: int32_t
value: 30000
mirror: always
# How long to be in interactive mode after an event.
- name: content.sink.interactive_time
type: uint32_t
value: 750000
mirror: always
# How long to stay in perf mode after initial loading.
- name: content.sink.initial_perf_time
type: uint32_t
value: 2000000
mirror: always
# Should we switch between perf-mode and interactive-mode?
# 0 = Switch
# 1 = Interactive mode
# 2 = Perf mode
- name: content.sink.enable_perf_mode
type: int32_t
value: 0
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "converter."
#---------------------------------------------------------------------------
# Whether we include ruby annotation in the text despite whether it
# is requested. This was true because we didn't explicitly strip out
# annotations. Set false by default to provide a better behavior, but
# we want to be able to pref-off it if user doesn't like it.
- name: converter.html2txt.always_include_ruby
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "cookiebanners."
#---------------------------------------------------------------------------
# Controls the cookie banner handling mode in normal browsing.
# 0: Disables all cookie banner handling.
# 1: Reject-all if possible, otherwise do nothing.
# 2: Reject-all if possible, otherwise accept-all.
- name: cookiebanners.service.mode
type: uint32_t
value: 0
mirror: always
# When set to true, cookie banners are detected and detection events are
# dispatched, but they will not be handled. Requires the service to be enabled
# for the desired mode via pref cookiebanners.service.mode*
- name: cookiebanners.service.detectOnly
type: bool
value: false
mirror: always
# Controls the cookie banner handling mode in private browsing. Same mode
# options as the normal browsing pref above.
- name: cookiebanners.service.mode.privateBrowsing
type: uint32_t
value: 0
mirror: always
# Enables use of global CookieBannerRules, which apply to all sites. This is
# used for click rules that can handle common Consent Management Providers
# (CMP).
# Enabling this (when the cookie handling feature is enabled) may negatively
# impact site performance since it requires us to run rule-defined query
# selectors for every page.
- name: cookiebanners.service.enableGlobalRules
type: bool
value: true
mirror: always
# Whether global rules are allowed to run in sub-frames. Running query selectors
# in every sub-frame may negatively impact performance, but is required for some
# CMPs.
- name: cookiebanners.service.enableGlobalRules.subFrames
type: bool
value: true
mirror: always
# Enables the cookie banner cookie injector. The cookie banner cookie injector
# depends on the `cookiebanners.service.mode` pref above.
- name: cookiebanners.cookieInjector.enabled
type: bool
value: true
mirror: always
# By default, how many seconds in the future cookies should expire after they
# have been injected. Defaults to 12 months. Individual cookie rules may
# override this.
- name: cookiebanners.cookieInjector.defaultExpiryRelative
type: uint32_t
value: 31536000
mirror: always
# How many times per site and site load to check for cookie banners after which
# the mechanism is considered on cooldown for the site in the current browsing
# session. If the threshold is set to zero, banner clicking won't be considered
# as being on cooldown regardless of how many times the site is loaded. The
# maximum value for the retry is 255, any value over than that will be capped.
- name: cookiebanners.bannerClicking.maxTriesPerSiteAndSession
type: uint32_t
value: 3
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "datareporting."
#---------------------------------------------------------------------------
# Do note that the toggle on Fenix and Focus does NOT reflect to this pref.
- name: datareporting.healthreport.uploadEnabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
#---------------------------------------------------------------------------
# Prefs starting with "device."
#---------------------------------------------------------------------------
# Is support for the device sensors API enabled?
- name: device.sensors.enabled
type: bool
value: true
mirror: always
- name: device.sensors.ambientLight.enabled
type: bool
value: false
mirror: always
- name: device.sensors.motion.enabled
type: bool
value: true
mirror: always
- name: device.sensors.orientation.enabled
type: bool
value: true
mirror: always
- name: device.sensors.proximity.enabled
type: bool
value: false
mirror: always
- name: device.sensors.test.events
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "devtools."
#---------------------------------------------------------------------------
- name: devtools.console.stdout.chrome
type: RelaxedAtomicBool
value: @IS_NOT_MOZILLA_OFFICIAL@
mirror: always
- name: devtools.console.stdout.content
type: RelaxedAtomicBool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "docshell."
#---------------------------------------------------------------------------
# Used to indicate whether session history listeners should be notified
# about content viewer eviction. Used only for testing.
- name: docshell.shistory.testing.bfevict
type: bool
value: false
mirror: always
# If true, pages with an opener won't be bfcached.
- name: docshell.shistory.bfcache.require_no_opener
type: bool
value: @IS_ANDROID@
mirror: always
# If true, page with beforeunload or unload event listeners can be bfcached.
- name: docshell.shistory.bfcache.allow_unload_listeners
type: bool
value: @IS_ANDROID@
mirror: always
# If true, page with beforeunload event listeners can be bfcached.
# This only works when sessionHistoryInParent is enabled.
- name: docshell.shistory.bfcache.ship_allow_beforeunload_listeners
type: bool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "dom."
#---------------------------------------------------------------------------
# Allow cut/copy
- name: dom.allow_cut_copy
type: bool
value: true
mirror: always
# Checks if offscreen animation throttling is enabled.
- name: dom.animations.offscreen-throttling
type: bool
value: true
mirror: always
# Should CommitStyles use the end-point inclusive timing?
- name: dom.animations.commit-styles-endpoint-inclusive
type: bool
value: false
mirror: always
# Is support for Navigator.getBattery enabled?
- name: dom.battery.enabled
type: bool
value: true
mirror: always
# Block multiple external protocol URLs in iframes per single event.
- name: dom.block_external_protocol_in_iframes
type: bool
value: true
mirror: always
# Block sandboxed BrowsingContexts from navigating to external protocols.
- name: dom.block_external_protocol_navigation_from_sandbox
type: bool
value: true
mirror: always
# Block Insecure downloads from Secure Origins
- name: dom.block_download_insecure
type: bool
value: true
mirror: always
# The maximum number of popup that is allowed to be opened. Set to -1 for no
# limit.
- name: dom.popup_maximum
type: int32_t
value: -1
mirror: always
# Enable CacheAPI in private browsing mode with encryption
- name: dom.cache.privateBrowsing.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Exposes window.caches and skips SecureContext check.
# dom.serviceWorkers.testing.enabled also includes the same effect.
- name: dom.caches.testing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# A pref that is used to slow down database initialization for testing purposes.
- name: dom.cache.databaseInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# Disable capture attribute for input elements; only supported on GeckoView.
- name: dom.capture.enabled
type: bool
value: false
mirror: always
# HTML specification says the level should be 5
- name: dom.clamp.timeout.nesting.level
type: uint32_t
value: 5
mirror: once
# Skip the security checks for document.cookie.
- name: dom.cookie.testing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.closewatcher.enabled
type: bool
value: false
mirror: always
# Disable custom highlight API; implementation pending.
- name: dom.customHighlightAPI.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
rust: true
# Allow control characters appear in composition string.
# When this is false, control characters except
# CHARACTER TABULATION (horizontal tab) are removed from
# both composition string and data attribute of compositionupdate
# and compositionend events.
- name: dom.compositionevent.allow_control_characters
type: bool
value: false
mirror: always
# Compression Streams (zstd) (CompressionStream/DecompressionStream)
# Whether or not "zstd" is a supported format for these streams.
- name: dom.compression_streams.zstd.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Disable cookie-store API
- name: dom.cookieStore.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Disable cookie-store manager API
- name: dom.cookieStore.manager.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Is support for CSSPseudoElement enabled?
- name: dom.css_pseudo_element.enabled
type: bool
value: false
mirror: always
# After how many seconds we allow external protocol URLs in iframe when not in
# single events
- name: dom.delay.block_external_protocol_in_iframes
type: uint32_t
value: 10 # in seconds
mirror: always
# Whether the above pref has any effect at all.
- name: dom.delay.block_external_protocol_in_iframes.enabled
type: bool
value: true
mirror: always
- name: dom.details_group.enabled
type: bool
value: true
mirror: always
# Only propagate the open window click permission if the setTimeout() is equal
# to or less than this value.
- name: dom.disable_open_click_delay
type: int32_t
value: 1000
mirror: always
- name: dom.disable_open_during_load
type: bool
value: false
mirror: always
- name: dom.disable_beforeunload
type: bool
value: false
mirror: always
- name: dom.require_user_interaction_for_beforeunload
type: bool
value: true
mirror: always
# Enable/disable Gecko specific edit commands
- name: dom.document.edit_command.contentReadOnly.enabled
type: bool
value: @IS_NOT_EARLY_BETA_OR_EARLIER@
mirror: always
- name: dom.document.edit_command.insertBrOnReturn.enabled
type: bool
value: @IS_NOT_EARLY_BETA_OR_EARLIER@
mirror: always
# Only intended for fuzzing purposes, this will break mozPrintCallback, etc.
- name: dom.window_print.fuzzing.block_while_printing
type: bool
value: false
mirror: always
# Whether Dialog elements emit beforetoggle and toggle events during opening and closing.
- name: dom.element.dialog.toggle_events.enabled
type: bool
value: true
mirror: always
- name: dom.element.transform-getters.enabled
type: bool
value: false
mirror: always
# Whether the blocking attribute implementation is enabled,
- name: dom.element.blocking.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Whether CustomStateSet is enabled
- name: dom.element.customstateset.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether the invoketarget attribute implementation is enabled
- name: dom.element.invokers.enabled
type: bool
value: false
mirror: always
- name: dom.mouse_capture.enabled
type: bool
value: true
mirror: always
# Is support for Performance.mozMemory enabled?
- name: dom.enable_memory_stats
type: bool
value: false
mirror: always
# Enable Performance API
# Whether nonzero values can be returned from performance.timing.*
- name: dom.enable_performance
type: RelaxedAtomicBool
value: true
mirror: always
# Enable Performance Observer API
- name: dom.enable_performance_observer
type: RelaxedAtomicBool
value: true
mirror: always
# Whether resource timing will be gathered and returned by performance.GetEntries*
- name: dom.enable_resource_timing
type: bool
value: true
mirror: always
# Whether event timing will be gathered and returned by performance observer*
- name: dom.enable_event_timing
type: RelaxedAtomicBool
value: true
mirror: always
# Whether the LargestContentfulPaint API will be gathered and returned by performance observer*
- name: dom.enable_largest_contentful_paint
type: RelaxedAtomicBool
value: true
mirror: always
# Whether performance.GetEntries* will contain an entry for the active document
- name: dom.enable_performance_navigation_timing
type: bool
value: true
mirror: always
# Whether the scheduler interface will be exposed
- name: dom.enable_web_task_scheduling
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# If this is true, it's allowed to fire "cut", "copy" and "paste" events.
# Additionally, "input" events may expose clipboard content when inputType
# is "insertFromPaste" or something.
- name: dom.event.clipboardevents.enabled
type: bool
value: true
mirror: always
# Whether Shift+Right click force-opens the context menu
- name: dom.event.contextmenu.shift_suppresses_event
type: bool
value: true
mirror: always
- name: dom.event.dragexit.enabled
type: bool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
# If this pref is set to true, typing a surrogate pair causes one `keypress`
# event whose `charCode` stores the unicode code point over 0xFFFF. This is
# compatible with Safari and Chrome in non-Windows platforms.
# Otherwise, typing a surrogate pair causes two `keypress` events. This is
# compatible with legacy web apps which does
# `String.fromCharCode(event.charCode)`.
- name: dom.event.keypress.dispatch_once_per_surrogate_pair
type: bool
value: false
mirror: always
# This is meaningful only when `dispatch_once_per_surrogate_pair` is false.
# If this pref is set to true, `.key` of the first `keypress` is set to the
# high-surrogate and `.key` of the other is set to the low-surrogate.
# Therefore, setting this exposing ill-formed UTF-16 string with `.key`.
# (And also `InputEvent.data` if pressed in an editable element.)
# Otherwise, `.key` of the first `keypress` is set to the surrogate pair, and
# `.key` of the second `keypress` is set to the empty string.
- name: dom.event.keypress.key.allow_lone_surrogate
type: bool
value: @IS_NOT_EARLY_BETA_OR_EARLIER@
mirror: always
# Whether the result of screenX, screenY, clientX, clientY, offsetX, offsetY,
# x and y of trusted MouseEvent and subclasses may be fractional values.
# Enabling this may cause backward compatibility issues.
# Note that this pref is referred only when
# `dom.event.pointer.fractional_coordinates.enabled` is `true`.
- name: dom.event.mouse.fractional_coordinates.trusted.enabled
type: bool
value: false
mirror: always
# Whether the result of screenX, screenY, clientX, clientY, offsetX, offsetY,
# x and y of untrusted MouseEvent and subclasses may be fractional values.
# I.e., this allows web apps to use fractional values with their own DOM events
# which have MouseEvent interface. However, this might cause backward
# compatibility issues if web apps initializes untrusted events with quotients.
# Note that this pref is referred only when
# `dom.event.pointer.fractional_coordinates.enabled` is `true`.
- name: dom.event.mouse.fractional_coordinates.untrusted.enabled
type: bool
value: false
mirror: always
# Whether the result of screenX, screenY, clientX, clientY, offsetX, offsetY,
# x and y of PointerEvent may be fractional values (except `click`, `auxclick`
# and `contextmenu`)
- name: dom.event.pointer.fractional_coordinates.enabled
type: bool
value: true
mirror: always
# Whether wheel event target's should be grouped. When enabled, all wheel
# events that occur in a given wheel transaction have the same event target.
- name: dom.event.wheel-event-groups.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Whether WheelEvent should return pixels instead of lines for
# WheelEvent.deltaX/Y/Z, when deltaMode hasn't been checked.
#
# Other browsers don't use line deltas and websites forget to check for it, see
- name: dom.event.wheel-deltaMode-lines.disabled
type: bool
value: true
mirror: always
# Mostly for debugging. Whether we should do the same as
# dom.event.wheel-deltaMode-lines.disabled, but unconditionally rather than
# only when deltaMode hasn't been checked.
- name: dom.event.wheel-deltaMode-lines.always-disabled
type: bool
value: false
mirror: always
# A blocklist (list of domains) for the
# dom.event.wheel-deltaMode-lines.disabled behavior, in case potential
# unforeseen problems with it arrive.
- name: dom.event.wheel-deltaMode-lines.always-enabled
type: String
value: ""
mirror: never
#if defined(XP_MACOSX)
# Whether to disable treating ctrl click as right click
- name: dom.event.treat_ctrl_click_as_right_click.disabled
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
#endif
# Whether .offset{X,Y} for events targeted at SVG nodes returns bounds relative
# to the outer SVG.
- name: dom.events.offset-in-svg-relative-to-svg-root
type: bool
value: true
mirror: always
# Control whether clipboard.read(), clipboard.write() and ClipboardItem are exposed
# to content.
- name: dom.events.asyncClipboard.clipboardItem
type: bool
value: true
mirror: always
# Skips checking permission and user activation when accessing the clipboard.
# Should only be enabled in tests.
# Access with Clipboard::IsTestingPrefEnabled().
- name: dom.events.testing.asyncClipboard
type: bool
value: false
mirror: always
do_not_use_directly: true
# Control whether `navigator.clipboard.readText()` is exposed to content.
- name: dom.events.asyncClipboard.readText
type: bool
value: true
mirror: always
do_not_use_directly: true
# This pref controls whether or not the `protected` dataTransfer state is
# enabled. If the `protected` dataTransfer stae is disabled, then the
# DataTransfer will be read-only whenever it should be protected, and will not
# be disconnected after a drag event is completed.
- name: dom.events.dataTransfer.protected.enabled
type: bool
value: false
mirror: always
# Whether to hide normal files (i.e. non-images) in dataTransfer inside
# the content process.
- name: dom.events.dataTransfer.mozFile.enabled
type: bool
value: true
mirror: always
- name: dom.events.dataTransfer.imageAsFile.enabled
type: bool
value: false
mirror: always
# User interaction timer interval, in ms
- name: dom.events.user_interaction_interval
type: uint32_t
value: 5000
mirror: always
# Whether to try to compress touchmove events on IPC layer.
- name: dom.events.compress.touchmove
type: bool
value: true
mirror: always
# In addition to the above IPC layer compresison, allow touchmove
# events to be further coalesced in the child side after they
# are sent.
- name: dom.events.coalesce.touchmove
type: bool
value: true
mirror: always
# Allow mousemove events to be coalesced in the child side after they are sent.
- name: dom.events.coalesce.mousemove
type: bool
value: true
mirror: always
# Expose Window.TextEvent and make the builtin editors dispatch `textInput`
# event as a default action of `beforeinput`.
- name: dom.events.textevent.enabled
type: bool
value: true
mirror: always
# Whether to dispatch `beforescriptexecute` and `afterscriptexecute` event.
- name: dom.events.script_execute.enabled
type: bool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
# Whether to expose test interfaces of various sorts
- name: dom.expose_test_interfaces
type: bool
value: false
mirror: always
- name: dom.fetchKeepalive.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# The maximum number of pending fetch keepalive requests per browser instance
- name: dom.fetchKeepalive.total_request_limit
type: RelaxedAtomicUint32
value: 2048
mirror: always
# The maximum number of pending fetch keepalive requests per origin
- name: dom.fetchKeepalive.request_limit_per_origin
type: RelaxedAtomicUint32
value: 256
mirror: always
- name: dom.fetchObserver.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to set the incremental flag on the top level document's
# priority header
- name: dom.document_priority.incremental
type: RelaxedAtomicBool
value: true
mirror: always
# Allow the content process to create a File from a path. This is allowed just
# on parent process, on 'file' Content process, or for testing.
- name: dom.file.createInChild
type: RelaxedAtomicBool
value: false
mirror: always
# Support @autocomplete values for form autofill feature.
- name: dom.forms.autocomplete.formautofill
type: bool
value: false
mirror: always
# Is support for HTMLElement.autocorrect enabled?
- name: dom.forms.autocorrect
type: bool
value: true
mirror: always
# Only trusted submit event could trigger form submission.
- name: dom.forms.submit.trusted_event_only
type: bool
value: false
mirror: always
# This pref just controls whether we format the number with grouping separator
# characters when the internal value is set or updated. It does not stop the
# user from typing in a number and using grouping separators.
- name: dom.forms.number.grouping
type: bool
value: false
mirror: always
# The interval in milliseconds between two Escape key events where the second
# key event will exit fullscreen, even if it is consumed.
- name: dom.fullscreen.force_exit_on_multiple_escape_interval
type: uint32_t
value: 500
mirror: always
# Whether the Gamepad API is enabled
- name: dom.gamepad.enabled
type: bool
value: true
mirror: always
# Is Gamepad Extension API enabled?
- name: dom.gamepad.extensions.enabled
type: bool
value: true
mirror: always
# Is LightIndicator API enabled in Gamepad Extension API?
- name: dom.gamepad.extensions.lightindicator
type: bool
value: false
mirror: always
# Is MultiTouch API enabled in Gamepad Extension API?
- name: dom.gamepad.extensions.multitouch
type: bool
value: false
mirror: always
# Is Gamepad vibrate haptic feedback function enabled?
- name: dom.gamepad.haptic_feedback.enabled
type: bool
value: true
mirror: always
- name: dom.gamepad.non_standard_events.enabled
type: bool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
- name: dom.gamepad.test.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# W3C draft ImageCapture API
- name: dom.imagecapture.enabled
type: bool
value: false
mirror: always
# The root margin for image lazy loading, defined as four (value, percentage)
# pairs.
- name: dom.image-lazy-loading.root-margin.top
type: float
value: 600
mirror: always
- name: dom.image-lazy-loading.root-margin.top.percentage
type: bool
value: false
mirror: always
- name: dom.image-lazy-loading.root-margin.bottom
type: float
value: 600
mirror: always
- name: dom.image-lazy-loading.root-margin.bottom.percentage
type: bool
value: false
mirror: always
- name: dom.image-lazy-loading.root-margin.left
type: float
value: 600
mirror: always
- name: dom.image-lazy-loading.root-margin.left.percentage
type: bool
value: false
mirror: always
- name: dom.image-lazy-loading.root-margin.right
type: float
value: 600
mirror: always
- name: dom.image-lazy-loading.root-margin.right.percentage
type: bool
value: false
mirror: always
# Enable indexedDB in private browsing mode with encryption
- name: dom.indexedDB.privateBrowsing.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# A pref that is used to slow down connection idle maintenance for testing
# purposes.
- name: dom.indexedDB.connectionIdleMaintenance.pauseOnConnectionThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# Whether or not indexedDB test mode is enabled.
- name: dom.indexedDB.testing
type: RelaxedAtomicBool
value: false
mirror: always
# Whether or not indexedDB experimental features are enabled.
- name: dom.indexedDB.experimental
type: RelaxedAtomicBool
value: false
mirror: always
# Whether or not indexedDB preprocessing is enabled.
- name: dom.indexedDB.preprocessing
type: RelaxedAtomicBool
value: false
mirror: always
# A pref that is used to slow down database initialization for testing purposes.
- name: dom.indexedDB.databaseInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# How innerWidth / innerHeight return rounded or fractional sizes.
#
# 0 or others: Do not round at all.
# 1: Round.
# 2: Truncate.
#
# NOTE(emilio): Fractional sizes are not web-compatible, see the regressions
# another API) one way or another, see [1], so we're keeping the code for the
# time being.
#
- name: dom.innerSize.rounding
type: uint32_t
value: 1
mirror: always
# Whether we conform to Input Events Level 1 or Input Events Level 2.
# true: conforming to Level 1
# false: conforming to Level 2
- name: dom.input_events.conform_to_level_1
type: bool
value: true
mirror: always
# Whether we allow BrowsingContextGroup to suspend input events
- name: dom.input_events.canSuspendInBCG.enabled
type: bool
value: false
mirror: always
# Whether dispatch a redundant `input` event before `compositionend`.
# Its `.isComposing` is `true`, but it might be useful to store the latest
# composition string before `compositionend` event listeners (although,
# `.data` of `compositionend` event contains the value.
- name: dom.input_events.dispatch_before_compositionend
type: bool
value: true
mirror: always
# The minimum number of ticks after page navigation
# that need to occur before user input events are allowed to be handled.
- name: dom.input_events.security.minNumTicks
type: uint32_t
value: 3
mirror: always
# The minimum elapsed time (in milliseconds) after page navigation
# for user input events are allowed to be handled.
- name: dom.input_events.security.minTimeElapsedInMS
type: uint32_t
value: 100
mirror: always
# By default user input handling delay is disabled (mostly) for testing ,
# this is used for forcefully enable it for certain tests.
- name: dom.input_events.security.isUserInputHandlingDelayTest
type: bool
value: false
mirror: always
# The maximum time (milliseconds) we reserve for handling input events in each
# frame.
- name: dom.input_event_queue.duration.max
type: uint32_t
value: 8
mirror: always
- name: dom.interactive_widget_default_resizes_visual
type: RelaxedAtomicBool
value: true
mirror: always
# How often to check for CPOW timeouts (ms). CPOWs are only timed
# out by the hang monitor.
- name: dom.ipc.cpow.timeout
type: uint32_t
value: 500
mirror: always
#ifdef MOZ_ENABLE_FORKSERVER
- name: dom.ipc.forkserver.enable
type: bool
#if defined(MOZ_CODE_COVERAGE) || defined(MOZ_ASAN) || defined(MOZ_TSAN) || defined(MOZ_MSAN) || defined(MOZ_UBSAN)
value: false
#else
value: @IS_NIGHTLY_BUILD@
#endif
mirror: once
#endif
#ifdef MOZ_WIDGET_GTK
#
# Avoid the use of GTK in content processes if possible, by running
# them in headless mode, to conserve resources (e.g., connections to
# the X server). See the usage in `ContentParent.cpp` for the full
# definition of "if possible".
#
# This does not affect sandbox policies; content processes may still
# dynamically connect to the display server for, e.g., WebGL.
- name: dom.ipc.avoid-gtk
type: bool
value: true
mirror: always
#endif
# Whether or not to collect a paired minidump when force-killing a
# content process.
- name: dom.ipc.tabs.createKillHardCrashReports
type: bool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: once
# Enable e10s hang monitoring (slow script checking and plugin hang detection).
- name: dom.ipc.processHangMonitor
type: bool
value: true
mirror: once
# Whether we report such process hangs
- name: dom.ipc.reportProcessHangs
type: RelaxedAtomicBool
# Don't report hangs in DEBUG builds. They're too slow and often a
# debugger is attached.
#ifdef DEBUG
value: false
#else
value: true
#endif
mirror: always
# If true, disables non-required re-use of content processes. This can be used
# in tests to force a new process to be used whenever a process selection
# decision is made. Setting this pref can cause dom.ipc.processCount limits to
# be exceeded.
# WARNING: This will exceed even process limits for the extension or
# privilegedAbout remote types, which may lead to unexpected breakage!
# Should only be used for testing.
- name: dom.ipc.disableContentProcessReuse
type: bool
value: false
mirror: always
# If non-zero, a grace delay (in milliseconds) during which unused content
# processes are kept available for re-use to avoid unnecessary process churn.
- name: dom.ipc.processReuse.unusedGraceMs
type: uint32_t
value: 0
mirror: always
# Process launch delay (in milliseconds).
- name: dom.ipc.processPrelaunch.delayMs
type: uint32_t
# This number is fairly arbitrary ... the intention is to put off
# launching another app process until the last one has finished
# loading its content, to reduce CPU/memory/IO contention.
value: 1000
mirror: always
- name: dom.ipc.processPrelaunch.startupDelayMs
type: uint32_t
# delay starting content processes for a short time after browser start
# to provide time for the UI to come up
value: 1000
mirror: always
# Process preallocation cache
# Only used in fission; in e10s we use 1 always
- name: dom.ipc.processPrelaunch.fission.number
type: uint32_t
value: 3
mirror: always
# Limit preallocated processes below this memory size (in MB)
- name: dom.ipc.processPrelaunch.lowmem_mb
type: uint32_t
value: 4096
mirror: always
- name: dom.ipc.processPriorityManager.enabled
type: bool
value: true
mirror: always
- name: dom.ipc.processPriorityManager.testMode
type: bool
value: false
mirror: always
- name: dom.ipc.processPriorityManager.backgroundPerceivableGracePeriodMS
type: uint32_t
#if defined(MOZ_WIDGET_ANDROID)
value: 3000
#else
value: 0
#endif
mirror: always
- name: dom.ipc.processPriorityManager.backgroundGracePeriodMS
type: uint32_t
#if defined(MOZ_WIDGET_ANDROID)
value: 3000
#else
value: 0
#endif
mirror: always
#ifdef XP_WIN
- name: dom.ipc.processPriorityManager.backgroundUsesEcoQoS
type: bool
value: false
mirror: always
#endif
# Support for input type=month, type=week. By default, disabled.
- name: dom.forms.datetime.others
type: bool
value: @IS_ANDROID@
mirror: always
- name: dom.forms.always_allow_pointer_events.enabled
type: bool
value: true
mirror: always
# Is support for key events and focus events on disabled elements enabled?
- name: dom.forms.always_allow_key_and_focus_events.enabled
type: bool
value: true
mirror: always
# Whether to disable only the descendants or the parent fieldset element too
# Note that this still allows it to be selected by `:disable`.
- name: dom.forms.fieldset_disable_only_descendants.enabled
type: bool
value: true
mirror: always
# Does mousewheel-scrolling over a focused <input type="number"> or
# <input type="range"> field cause the value to increase/decrease (rather
# than scrolling the page)?
- name: dom.input.number_and_range_modified_by_mousewheel
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to allow or disallow web apps to cancel `beforeinput` events caused
# by MozEditableElement#setUserInput() which is used by autocomplete, autofill
# and password manager.
- name: dom.input_event.allow_to_cancel_set_user_input
type: bool
value: false
mirror: always
# How long a content process can take before closing its IPC channel
# after shutdown is initiated. If the process exceeds the timeout,
# we fear the worst and kill it.
- name: dom.ipc.tabs.shutdownTimeoutSecs
type: RelaxedAtomicUint32
#if !defined(DEBUG) && !defined(MOZ_ASAN) && !defined(MOZ_VALGRIND) && !defined(MOZ_TSAN)
value: 20
#else
value: 0
#endif
mirror: always
# Whether a native event loop should be used in the content process.
- name: dom.ipc.useNativeEventProcessing.content
type: RelaxedAtomicBool
#if defined(XP_WIN) || defined(XP_DARWIN)
value: false
#else
value: true
#endif
mirror: always
# If this is true, TextEventDispatcher dispatches keydown and keyup events
# even during composition (keypress events are never fired during composition
# even if this is true).
- name: dom.keyboardevent.dispatch_during_composition
type: bool
value: true
mirror: always
# Enable/disable KeyboardEvent.initKeyEvent function
- name: dom.keyboardevent.init_key_event.enabled
type: bool
value: false
mirror: always
# Enable/disable KeyboardEvent.initKeyEvent function in addons even if it's
# disabled.
- name: dom.keyboardevent.init_key_event.enabled_in_addons
type: bool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
# If this is true, keypress events for non-printable keys are dispatched only
# for event listeners of the system event group in web content.
- name: dom.keyboardevent.keypress.dispatch_non_printable_keys_only_system_group_in_content
type: bool
value: true
mirror: always
# If this is true, "keypress" event's keyCode value and charCode value always
# become same if the event is not created/initialized by JS.
- name: dom.keyboardevent.keypress.set_keycode_and_charcode_to_same_value
type: bool
value: true
mirror: always
# Whether "W3C Web Manifest" processing is enabled
- name: dom.manifest.enabled
type: bool
value: true
mirror: always
# Enable mapped array buffer by default.
- name: dom.mapped_arraybuffer.enabled
type: bool
value: true
mirror: always
- name: dom.media.autoplay-policy-detection.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# WebCodecs API
- name: dom.media.webcodecs.enabled
type: RelaxedAtomicBool
#if defined(MOZ_WIDGET_ANDROID)
value: @IS_NIGHTLY_BUILD@
#else
value: true
#endif
mirror: always
# WebCodecs API - Image decoder
- name: dom.media.webcodecs.image-decoder.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# WebCodecs API - H265
- name: dom.media.webcodecs.h265.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Number of seconds of very quiet or silent audio before considering the audio
# inaudible.
- name: dom.media.silence_duration_for_audibility
type: AtomicFloat
value: 2.0f
mirror: always
# Inform mozjemalloc that the foreground content processes can keep more dirty
# pages in memory.
- name: dom.memory.foreground_content_processes_have_larger_page_cache
type: bool
value: true
mirror: always
# 0 no-op
# 1 free dirty mozjemalloc pages
# 2 trigger memory-pressure/heap-minimize
# 3 trigger memory-pressure/low-memory
- name: dom.memory.memory_pressure_on_background
type: uint32_t
value: 0
mirror: always
# Enable meta-viewport support in remote APZ-enabled frames.
- name: dom.meta-viewport.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Timeout clamp in ms for timeouts we clamp.
- name: dom.min_timeout_value
type: RelaxedAtomicInt32
value: 4
mirror: always
# Timeout clamp in ms for background windows.
- name: dom.min_background_timeout_value
type: int32_t
value: 1000
mirror: always
# Timeout clamp in ms for background windows when throttling isn't enabled.
- name: dom.min_background_timeout_value_without_budget_throttling
type: int32_t
value: 1000
mirror: always
# Are missing-property use counters for certain DOM attributes enabled?
- name: dom.missing_prop_counters.enabled
type: bool
value: true
mirror: always
# Whether to dispatch mutation events.
- name: dom.mutation_events.enabled
type: bool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
# Limit of location change caused by content scripts in a time span per
# BrowsingContext. This includes calls to History and Location APIs.
- name: dom.navigation.navigationRateLimit.count
type: uint32_t
value: 200
mirror: always
# Time span in seconds for location change rate limit.
- name: dom.navigation.navigationRateLimit.timespan
type: uint32_t
value: 10
mirror: always
# Whether to allow <object> and <embed> element loads to be retargeted to an
# external application or download.
- name: dom.navigation.object_embed.allow_retargeting
type: bool
value: false
mirror: always
# Whether the navigation API will be exposed.
- name: dom.navigation.webidl.enabled
type: RelaxedAtomicBool
value: false
mirror: always
do_not_use_directly: true
# Network Information API
# This feature is not available on Firefox desktop. It exposes too much
# user information. Let's be consistent and disable it on Android.
# But let's keep it around in case it becomes necessary for webcompat
# reasons
- name: dom.netinfo.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Whether we should open noopener links in a new process.
- name: dom.noopener.newprocess.enabled
type: bool
value: true
mirror: always
# Whether origin trials are enabled.
- name: dom.origin-trials.enabled
type: bool
value: true
mirror: always
# Whether we use the test key to verify tokens.
- name: dom.origin-trials.test-key.enabled
type: bool
value: false
mirror: always
# Origin trial state for "TestTrial".
# 0: normal, 1: always-enabled, 2: always-disabled
- name: dom.origin-trials.test-trial.state
type: RelaxedAtomicInt32
value: 0
mirror: always
# Origin trial state for COEP: Credentialless.
# 0: normal, 1: always-enabled, 2: always-disabled
- name: dom.origin-trials.coep-credentialless.state
type: RelaxedAtomicInt32
value: 0
mirror: always
# Origin trial state for Private Attribution
# 0: normal, 1: always-enabled, 2: always-disabled
- name: dom.origin-trials.private-attribution.state
type: RelaxedAtomicInt32
#ifdef ANDROID
value: 2
#else
value: 0
#endif
mirror: always
# Origin trial state for MLS
# 0: normal, 1: always-enabled, 2: always-disabled
- name: dom.origin-trials.mls.state
type: RelaxedAtomicInt32
value: 0
mirror: always
# User pref to control whether Private Attribution
# information should be collected / submitted.
- name: dom.private-attribution.submission.enabled
type: bool
value: @IS_NOT_ANDROID@
mirror: always
# Is support for Window.paintWorklet enabled?
- name: dom.paintWorklet.enabled
type: bool
value: false
mirror: always
# Enable/disable the PaymentRequest API
- name: dom.payments.request.enabled
type: bool
value: false
mirror: always
# Whether a user gesture is required to call PaymentRequest.prototype.show().
- name: dom.payments.request.user_interaction_required
type: bool
value: true
mirror: always
# Time in milliseconds for PaymentResponse to wait for
# the Web page to call complete().
- name: dom.payments.response.timeout
type: uint32_t
value: 5000
mirror: always
# Enable printing performance marks/measures to log
- name: dom.performance.enable_user_timing_logging
type: RelaxedAtomicBool
value: false
mirror: always
# Enable notification of performance timing
- name: dom.performance.enable_notify_performance_timing
type: bool
value: false
mirror: always
# Is support for PerformanceTiming.timeToContentfulPaint enabled?
- name: dom.performance.time_to_contentful_paint.enabled
type: bool
value: false
mirror: always
# Is support for PerformanceTiming.timeToFirstInteractive enabled?
- name: dom.performance.time_to_first_interactive.enabled
type: bool
value: false
mirror: always
# Is support for PerformanceTiming.timeToNonBlankPaint enabled?
- name: dom.performance.time_to_non_blank_paint.enabled
type: bool
value: false
mirror: always
# Whether the interactionId will be computed and returned by performance observer*
- name: dom.performance.event_timing.enable_interactionid
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Is support for Element.requestPointerLock enabled?
# This is added for accessibility purpose. When user has no way to exit
# pointer lock (e.g. no keyboard available), they can use this pref to
# disable the Pointer Lock API altogether.
- name: dom.pointer-lock.enabled
type: bool
value: true
mirror: always
# re-SAB: Whether to allow postMessage of a SharedArrayBuffer if various
# preconditions related to COOP and COEP are met
- name: dom.postMessage.sharedArrayBuffer.withCOOP_COEP
type: bool
value: true
mirror: once
# Overridden in all.js on RELEASE_OR_BETA in order to add the locked attribute.
- name: dom.postMessage.sharedArrayBuffer.bypassCOOP_COEP.insecure.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Should we speculatively prefetch dns for anchor elements on http documents
- name: dom.prefetch_dns_for_anchor_http_document
type: bool
value: true
mirror: always
# Should we speculatively prefetch dns for anchor elements on https documents
- name: dom.prefetch_dns_for_anchor_https_document
type: bool
value: false
mirror: always
# This currently only affects XHTML. For XUL the cache is always allowed.
- name: dom.prototype_document_cache.enabled
type: bool
value: true
mirror: always
# Push
- name: dom.push.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Indicate the deprecated aesgcm support in PushManager.supportedContentEncodings.
#
# This does not affect actual aesgcm support, any new and existing subscriptions
# can still use aesgcm regardless of this pref.
- name: dom.push.indicate_aesgcm_support.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Preference that is primarily used for testing of problematic file paths.
# It can also be used for switching between different storage directories, but
# such feature is not officially supported.
- name: dom.quotaManager.storageName
type: String
value: "storage"
mirror: never
# An upper limit for the "age" of an origin. Any origin which is older than the
# threshold is considered as unaccessed. That doesn't necessarily mean that
# such origins will be immediatelly archived. They will be archived only when
# dom.quotaManager.checkQuotaInfoLoadTime is true and loading of quota info
# takes a long time (dom.quotaManager.longQuotaInfoLoadTimeThresholdMs is used
# to decide what is a long quota info load time).
- name: dom.quotaManager.unaccessedForLongTimeThresholdSec
type: RelaxedAtomicUint32
value: 33696000 # 13 months
mirror: always
# Should we try to load origin information from the cache?
- name: dom.quotaManager.loadQuotaFromCache
type: RelaxedAtomicBool
value: true
mirror: always
# Should we check build ID as part of the cache validation?
# When enabled, the cache is invalidated on any upgrade (or downgrade),
# ensuring that changes in how quota usage is calculated can't cause
# inconsistencies at the cost of a slower initialization. Currently, this
# should only be set to false in tests using a packaged profile that inherently
# includes a build id different from the building running the tests. In the
# future this may be set to false if we are confident that we have sufficiently
# thorough schema versioning.
- name: dom.quotaManager.caching.checkBuildId
type: RelaxedAtomicBool
value: true
mirror: always
# Should we check quota info load time and eventually archive some unaccessed
# origins if loading of quota info takes a long time ?
- name: dom.quotaManager.checkQuotaInfoLoadTime
type: RelaxedAtomicBool
value: true
mirror: always
# An upper limit for quota info load time, anything which takes longer than the
# threshold is considered as long quota info load time.
- name: dom.quotaManager.longQuotaInfoLoadTimeThresholdMs
type: RelaxedAtomicUint32
value: 21000 # 21 seconds
mirror: always
# Preference that users can set to override temporary storage smart limit
# calculation.
- name: dom.quotaManager.temporaryStorage.fixedLimit
type: RelaxedAtomicInt32
value: -1
mirror: always
# Controls whether the quota manager updates the last access time for origins
# in temporary storage. When enabled, the access time is updated only when an
# origin is accessed by a quota client for the first time during a session or
# when the last quota client stops accessing the origin. This allows eviction
# based on the LRU policy. When disabled, the access time is stored only once
# when the corresponding origin directory is created for the first time.
#
# This setting is currently intended for manual testing purposes only.
- name: dom.quotaManager.temporaryStorage.updateOriginAccessTime
type: RelaxedAtomicBool
value: true
mirror: always
# Should we do lazy initialization of origins ?
# When enabled, origins for temporary storage are not initialized during
# temporary storage initialization, they are initialized lazily instead.
# If there are other origins in the group, they are initialized all together.
# This feature is currently still in development and experimental, not
# recommended for normal use yet.
#
# Note: If dom.quotaManager.temporaryStorage.incrementalOriginInitialization
# is set to true, this preference will be overridden, and the individual
# setting will no longer take effect, regardless of its value.
- name: dom.quotaManager.temporaryStorage.lazyOriginInitialization
type: RelaxedAtomicBool
value: false
mirror: always
do_not_use_directly: true
# Should we trigger initialization of all temporary origins in the background?
# When enabled, temporary origins collected during temporary storage
# initialization are initialized in the background. The background
# initialization of temporary origins is always done for entire groups of
# origins to preserve consistency of quota checks related to the group limit.
# This feature is currently still in development and experimental, not
# recommended for normal use yet.
#
# Note: If dom.quotaManager.temporaryStorage.incrementalOriginInitialization
# is set to true, this preference will be overridden, and the individual
# setting will no longer take effect, regardless of its value.
- name: dom.quotaManager.temporaryStorage.triggerOriginInitializationInBackground
type: RelaxedAtomicBool
value: false
mirror: always
do_not_use_directly: true
# Should we enable incremental initialization of origins? (also known as
# asynchronous temporary storage initialization)
# When enabled, this preference acts as an override for the following
# preferences:
# - dom.quotaManager.temporaryStorage.lazyOriginInitialization
# - dom.quotaManager.temporaryStorage.triggerOriginInitializationInBackground
#
# Enabling this preference ensures that:
# 1. Origins for temporary storage are not initialized during temporary storage
# initialization but are instead initialized incrementally, either lazily or
# in the background, depending on which occurs first.
# 2. Background initialization of temporary origins is triggered after the
# temporary storage initialization. The process is carried out in steps,
# with each step being responsible for initializing a group of origins.
#
# See also the documentation for those two preferences for more details on
# their individual behaviors.
#
# This feature is currently in development and experimental, not recommended
# for normal use yet.
- name: dom.quotaManager.temporaryStorage.incrementalOriginInitialization
type: RelaxedAtomicBool
value: false
mirror: always
do_not_use_directly: true
# A pref that is used to slow down origin operations for testing purposes.
- name: dom.quotaManager.originOperations.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# A pref that is used to slow down storage initialization for testing purposes.
- name: dom.quotaManager.storageInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# A pref that is used to slow down group initialization for testing purposes.
- name: dom.quotaManager.groupInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# A pref that is used to slow down origin initialization for testing purposes.
- name: dom.quotaManager.originInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# A pref that is used to enable testing features.
- name: dom.quotaManager.testing
type: SequentiallyConsistentAtomicBool
value: false
mirror: always
#if defined(XP_WIN)
# Preference that is used to set nsILocalFileWin::useDOSDevicePathSyntax
# attribute for all local file instances created by QuotaManager and its
# clients. The value of this preference is cached so changing the preference
# during runtime has no effect.
- name: dom.quotaManager.useDOSDevicePathSyntax
type: RelaxedAtomicBool
value: true
mirror: always
do_not_use_directly: true
# Preference that is used to enable the hack for overrriding xFullPathname in
# QuotaVFS.
- name: dom.quotaManager.overrideXFullPathname
type: RelaxedAtomicBool
value: true
mirror: always
#elif defined(XP_UNIX)
# Preference that is used to enable the overriding of Unix xFullPathname
# implementation in QuotaVFS.
- name: dom.quotaManager.overrideXFullPathnameUnix
type: RelaxedAtomicBool
value: true
mirror: always
#endif
# How many times we should retry directory removal or renaming if access was
# denied?
- name: dom.quotaManager.directoryRemovalOrRenaming.maxRetries
type: RelaxedAtomicUint32
#ifdef XP_WIN
value: 10
#else
value: 0
#endif
mirror: always
# How long we should wait between retries (in milliseconds)?
- name: dom.quotaManager.directoryRemovalOrRenaming.delayMs
type: RelaxedAtomicUint32
value: 200
mirror: always
#ifdef MOZ_BACKGROUNDTASKS
# Use a Background Task to delete files at shutdown.
- name: dom.quotaManager.backgroundTask.enabled
type: bool
#ifdef XP_MACOSX
value: false
#else
value: true
#endif
mirror: never
#endif
# A pref that specifies one or more failure categories to trigger artificial
# failures for testing purposes. Multiple categories can be combined using
# bitwise OR to represent various failure points within the code.
- name: dom.quotaManager.artificialFailure.categories
type: RelaxedAtomicUint32
value: 0
mirror: always
# A probability (0-100) used to determine the likelihood of triggering an
# artificial failure for testing purposes. This value is applied when the
# specified failure categories match to decide if the failure should occur.
- name: dom.quotaManager.artificialFailure.probability
type: RelaxedAtomicUint32
value: 0
mirror: always
# An error code used to trigger an artificial failure for testing purposes.
# This code is returned when the specified failure categories match and the
# failure is triggered based on the configured probability.
- name: dom.quotaManager.artificialFailure.errorCode
type: RelaxedAtomicUint32
value: 0
mirror: always
# Use to control to dump CheckedUnsafePtr creation stack and assignment stacks.
- name: dom.checkedUnsafePtr.dumpStacks.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# A pref that is used to slow down database initialization for testing purposes.
- name: dom.simpledb.databaseInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# Determines within what distance of a tick mark, in pixels, dragging an input
# range range will snap the range's value to that tick mark. By default, this is
# half the default width of the range thumb.
- name: dom.range_element.magnet_effect_threshold
type: float
value: 10.0f
mirror: always
# Reporting API.
- name: dom.reporting.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.reporting.testing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.reporting.featurePolicy.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.reporting.crash.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.reporting.header.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# In seconds. The timeout to remove not-active report-to endpoints.
- name: dom.reporting.cleanup.timeout
type: uint32_t
value: 3600
mirror: always
# Any X seconds the reports are dispatched to endpoints.
- name: dom.reporting.delivering.timeout
type: uint32_t
value: 5
mirror: always
# How many times the delivering of a report should be tried.
- name: dom.reporting.delivering.maxFailures
type: uint32_t
value: 3
mirror: always
# How many reports should be stored in the report queue before being delivered.
- name: dom.reporting.delivering.maxReports
type: uint32_t
value: 100
mirror: always
# Enable Screen Orientation lock
- name: dom.screenorientation.allow-lock
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Enable Screen Wake Lock API
- name: dom.screenwakelock.enabled
type: bool
value: true
mirror: always
# Whether to enable the JavaScript start-up cache. This causes one of the first
# execution to record the bytecode of the JavaScript function used, and save it
# in the existing cache entry. On the following loads of the same script, the
# bytecode would be loaded from the cache instead of being generated once more.
- name: dom.script_loader.bytecode_cache.enabled
type: bool
value: true
mirror: always
# Ignore the heuristics of the bytecode cache, and always record on the first
# visit. (used for testing purposes).
# Choose one strategy to use to decide when the bytecode should be encoded and
# saved. The following strategies are available right now:
# * -2 : (reader mode) The bytecode cache would be read, but it would never
# be saved.
# * -1 : (eager mode) The bytecode would be saved as soon as the script is
# seen for the first time, independently of the size or last access
# time.
# * 0 : (default) The bytecode would be saved in order to minimize the
# page-load time.
#
# Other values might lead to experimental strategies. For more details, have a
# look at: ScriptLoader::ShouldCacheBytecode function.
- name: dom.script_loader.bytecode_cache.strategy
type: int32_t
value: 0
mirror: always
# Select which parse/delazification strategy should be used while parsing
# scripts off-main-thread. (see CompileOptions.h, DelazificationOption enum)
#
# 0: On-demand only. Delazification will be triggered only on the main thread
# before the execution of the function.
#
# 1: Compare on-demand delazification (= 0) with concurrent depth-first
# delazification (= 2).
#
# 2: Depth-first. Delazify all functions off-thread in the order of appearance
# in the source.
#
# 3: Large-first. Delazify all functions off-thread starting with the largest
# functions first, and the smallest as the last one to be delazified, where
# the size of function is measured in bytes between the start to the end of
# the function.
#
# 255: Parse everything eagerly, from the first parse. All functions are parsed
# at the same time as the top-level of a file.
- name: dom.script_loader.delazification.strategy
type: uint32_t
value: 255
mirror: always
# Maximum total size after which the delazification strategy, specified by
# `dom.script_loader.delazification.strategy`, is no longer applied, and the
# on-demand strategy is used by default.
#
# -1 disable the threshold, and delazification strategy is applied to all
# scripts.
#
# Default value is 10MB for utf8 scripts.
- name: dom.script_loader.delazification.max_size
type: int32_t
value: 10485760
mirror: always
# Minimum memory, in GB, required to enable delazification strategy, specified
# by `dom.script_loader.delazification.strategy`. Otherwise, the on-demand
# delazification strategy is used.
- name: dom.script_loader.delazification.min_mem
type: int32_t
value: 2
mirror: always
# Enable speculative off main thread parsing of external scripts as
# soon as they are fetched.
- name: dom.script_loader.external_scripts.speculative_omt_parse.enabled
type: bool
value: true
mirror: always
# Speculatively compile non parser inserted scripts
- name: dom.script_loader.external_scripts.speculate_non_parser_inserted.enabled
type: bool
value: false
mirror: always
# Speculatively compile async scripts
- name: dom.script_loader.external_scripts.speculate_async.enabled
type: bool
value: false
mirror: always
# Speculatively compile link preload scripts
- name: dom.script_loader.external_scripts.speculate_link_preload.enabled
type: bool
value: false
mirror: always
# Cache stencil across navigation
- name: dom.script_loader.navigation_cache
type: bool
value: false
mirror: always
- name: dom.securecontext.allowlist_onions
type: bool
value: false
mirror: always
# This pref enables the featurePolicy header support.
- name: dom.security.featurePolicy.header.enabled
type: bool
value: false
mirror: always
- name: dom.security.featurePolicy.experimental.enabled
type: bool
value: false
mirror: always
# Expose the 'featurePolicy' attribute in document and HTMLIFrameElement
- name: dom.security.featurePolicy.webidl.enabled
type: bool
value: false
mirror: always
# Perform IPC based Principal vetting in ContentParent
- name: dom.security.enforceIPCBasedPrincipalVetting
type: RelaxedAtomicBool
value: true
mirror: always
# For testing purposes only: Flipping this pref to true allows
# to skip the allowlist for about: pages and do not ship with a
# CSP and NS_ASSERT right away.
- name: dom.security.skip_about_page_csp_allowlist_and_assert
type: RelaxedAtomicBool
value: false
mirror: always
# For testing purposes only: Flipping this pref to true allows
# to skip the assertion that every about page ships with a CSP.
- name: dom.security.skip_about_page_has_csp_assert
type: RelaxedAtomicBool
value: false
mirror: always
# For testing purposes only: Flipping this pref to true allows
# to skip the assertion that HTML fragments (e.g. innerHTML) can
# not be used within chrome code or about: pages.
- name: dom.security.skip_html_fragment_assertion
type: RelaxedAtomicBool
value: false
mirror: always
# For testing purposes only; Flipping this pref to true allows
# to skip the assertion that remote scripts can not be loaded
# in system privileged contexts.
- name: dom.security.skip_remote_script_assertion_in_system_priv_context
type: RelaxedAtomicBool
value: false
mirror: always
# If and only if true, support for Trusted Types
- name: dom.security.trusted_types.enabled
type: RelaxedAtomicBool
value: False
mirror: always
# If true, all content requests will get upgraded to HTTPS://
# (some Firefox functionality requests, like OCSP will not be affected)
- name: dom.security.https_only_mode
type: RelaxedAtomicBool
value: false
mirror: always
# If true, all content requests in Private Browsing Mode will get
# upgraded to HTTPS://. (If dom.security.https_only_mode is set
# to true then this pref has no effect)
- name: dom.security.https_only_mode_pbm
type: RelaxedAtomicBool
value: false
mirror: always
# If true, sends http background request for top-level sites to
# counter long timeouts.
- name: dom.security.https_only_mode_send_http_background_request
type: RelaxedAtomicBool
value: true
mirror: always
# Time limit, in milliseconds, before sending the http background
# request for HTTPS-Only and HTTPS-First
- name: dom.security.https_only_fire_http_request_background_timer_ms
type: RelaxedAtomicUint32
value: 2200
mirror: always
# If true, tries to break upgrade downgrade cycles where https-only tries
# to upgrad ethe connection, but the website tries to downgrade again.
- name: dom.security.https_only_mode_break_upgrade_downgrade_endless_loop
type: RelaxedAtomicBool
value: true
mirror: always
# If true and HTTPS-only mode is enabled, requests
# to local IP addresses are also upgraded
- name: dom.security.https_only_mode.upgrade_local
type: RelaxedAtomicBool
value: false
mirror: always
# If true and HTTPS-only mode is enabled, requests
# to .onion hosts are also upgraded
- name: dom.security.https_only_mode.upgrade_onion
type: RelaxedAtomicBool
value: false
mirror: always
# WARNING: Don't ever update that pref manually! It is only used
# for telemetry purposes and allows to reason about retention of
# the pref dom.security.https_only_mode from above.
- name: dom.security.https_only_mode_ever_enabled
type: RelaxedAtomicBool
value: false
mirror: always
# WARNING: Don't ever update that pref manually! It is only used
# for telemetry purposes and allows to reason about retention of
# the pref dom.security.https_only_mode_pbm from above.
- name: dom.security.https_only_mode_ever_enabled_pbm
type: RelaxedAtomicBool
value: false
mirror: always
# If true checks for secure www connections when https fails
# and gives the user suggestions on the error page
- name: dom.security.https_only_mode_error_page_user_suggestions
type: RelaxedAtomicBool
value: false
mirror: always
# If true, top-level request will get upgraded to HTTPS and
# downgraded again if the request failed.
- name: dom.security.https_first
type: RelaxedAtomicBool
value: true
mirror: always
# If true, HTTPS-First will upgrade non-default ports
- name: dom.security.https_first_for_custom_ports
type: RelaxedAtomicBool
value: false
mirror: always
# If true, HTTPS-First will upgrade local addresses
- name: dom.security.https_first_for_local_addresses
type: RelaxedAtomicBool
value: false
mirror: always
# If true, HTTPS-First will upgrade unknown suffixes
- name: dom.security.https_first_for_unknown_suffixes
type: RelaxedAtomicBool
value: false
mirror: always
# If true, top-level requests in Private Browsing Mode will get
# upgraded to HTTPS. (If dom.security.https_first
# is set to true then this pref has no effect)
- name: dom.security.https_first_pbm
type: RelaxedAtomicBool
value: true
mirror: always
# If true, top-level requests that are initiated from the address
# bar and with an empty scheme get upgraded to HTTPS
# with a fallback
- name: dom.security.https_first_schemeless
type: RelaxedAtomicBool
value: true
mirror: always
# If true, will add a special temporary HTTPS-First exception for a site when a
# HTTPS-First upgrade fails.
- name: dom.security.https_first_add_exception_on_failure
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.security.https_first_exception_lifetime
type: uint32_t
value: 7*24*60*60*1000 # 7 days in milliseconds
mirror: always
- name: dom.security.unexpected_system_load_telemetry_enabled
type: bool
value: @IS_EARLY_BETA_OR_EARLIER@
mirror: always
# pref controls `Sanitizer` API being exposed
- name: dom.security.sanitizer.enabled
type: bool
value: false
mirror: always
# Logs elements and attributes removed by the Sanitizer API to the console.
- name: dom.security.sanitizer.logging
type: bool
value: false
mirror: always
# pref controls credential chooser UI for testing. When true, UI is not shown and
# either a credential with ID `wpt-pick-me` is selected, or none.
- name: dom.security.credentialmanagement.chooser.testing.enabled
type: bool
value: false
mirror: always
# pref controls `identity` credentials being exposed
- name: dom.security.credentialmanagement.identity.enabled
type: bool
value: false
mirror: always
# pref controls "heavyweight" network discoverable `identity` credentials being exposed
- name: dom.security.credentialmanagement.identity.heavyweight.enabled
type: bool
value: false
mirror: always
# pref controls storable "lightweight" `identity` credentials being exposed
- name: dom.security.credentialmanagement.identity.lightweight.enabled
type: bool
value: false
mirror: always
# pref controls `identity` credential UI for testing. When true, UI is not shown and
# the first option in the account and provider lists are chosen
- name: dom.security.credentialmanagement.identity.select_first_in_ui_lists
type: bool
value: false
mirror: always
# pref controls `identity` credential platform behavior for testing. When true,
# the .well-known file check is not performed.
- name: dom.security.credentialmanagement.identity.test_ignore_well_known
type: bool
value: false
mirror: always
# pref controls whether we should delay identity credential rejections at all
- name: dom.security.credentialmanagement.identity.reject_delay.enabled
type: bool
value: true
mirror: always
# pref controls how long we should delay identity credential rejections if enabled
- name: dom.security.credentialmanagement.identity.reject_delay.duration_ms
type: uint32_t
value: 120000
mirror: always
# Enforce origin check whenever a content process tries to set a document URI
- name: dom.security.setdocumenturi
type: bool
value: true
mirror: always
# Whether or not selection events on text controls are enabled.
- name: dom.select_events.textcontrols.selectionchange.enabled
type: bool
value: true
mirror: always
- name: dom.select_events.textcontrols.selectstart.enabled
type: bool
value: false
mirror: always
- name: dom.select.showPicker.enabled
type: bool
value: true
mirror: always
- name: dom.send_after_paint_to_content
type: bool
value: false
mirror: always
- name: dom.separate_event_queue_for_post_message.enabled
type: bool
value: true
mirror: always
- name: dom.arena_allocator.enabled
type: bool
value: true
mirror: once
- name: dom.serviceWorkers.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.serviceWorkers.navigationPreload.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Mitigates ServiceWorker navigation faults by bypassing the ServiceWorker on
# navigation faults. This is more extensive than just resetting interception
# because we also mark the page as uncontrolled so that subresources will not
# go to the ServiceWorker either.
- name: dom.serviceWorkers.mitigations.bypass_on_fault
type: bool
value: true
mirror: always
# Additional ServiceWorker navigation mitigation control to unregister the
# ServiceWorker after multiple faults are encountered. The mitigation is
# disabled when this is set to zero, otherwise this is the number of faults that
# need to occur for a specific ServiceWorker before it will be unregistered.
- name: dom.serviceWorkers.mitigations.navigation_fault_threshold
type: uint32_t
value: 3
mirror: always
# This is the group usage head room for service workers.
# The quota usage mitigation algorithm uses this preference to determine if the
# origin or also group data should be cleared or not.
# The default value is 400 MiB.
- name: dom.serviceWorkers.mitigations.group_usage_headroom_kb
type: uint32_t
value: 400 * 1024
mirror: always
# Enable ServiceWorkers in Private Browsing Mode (PBM). This requires
# dom.cache.privateBrowsing.enabled to be enabled as well. Registrations are
# not persisted to disk; installed scripts are stored in Cache API storage which
# is encrypted in PBM.
- name: dom.serviceWorkers.privateBrowsing.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
- name: dom.serviceWorkers.testing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Whether ServiceWorkerManager should persist the service worker
# registered by temporary installed extension (only meant to be used
# for testing purpose, to make it easier to test some particular scenario
# with a temporary installed addon, which doesn't need to be signed to be
# installed on release channel builds).
- name: dom.serviceWorkers.testing.persistTemporarilyInstalledAddons
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.storage.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.workers.pFetch.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.workers.importScripts.enforceStrictMimeType
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.workers.throttling.enabled
type: bool
value: false
mirror: once
- name: dom.workers.timeoutmanager
type: bool
value: true
mirror: once
- name: dom.workers.serialized-sab-access
type: RelaxedAtomicBool
value: false
mirror: always
# Enable stronger diagnostics on worker shutdown.
# If this is true, we will potentially run an extra GCCC when a worker should
# exit its DoRunLoop but holds any WorkerRef and we will MOZ_DIAGNOSTIC_ASSERT
# when during that extra GCCC such a WorkerRef is freed.
- name: dom.workers.GCCC_on_potentially_last_event
type: RelaxedAtomicBool
#if defined(FUZZING) || defined(DEBUG)
value: true
#else
value: false
#endif
mirror: always
- name: dom.sitepermsaddon-provider.enabled
type: bool
value: @IS_NOT_ANDROID@
mirror: always
# Server-Sent Events
# Equal to the DEFAULT_RECONNECTION_TIME_VALUE value in nsEventSource.cpp
- name: dom.serverEvents.defaultReconnectionTime
type: RelaxedAtomicUint32
value: 5000 # in milliseconds
mirror: always
# Whether automatic storage access granting heuristics should be turned on.
- name: dom.storage_access.auto_grants
type: bool
value: true
mirror: always
- name: dom.storage_access.auto_grants.delayed
type: bool
value: true
mirror: always
# Whether to exclude third-party trackers from Storage Access API auto grants.
- name: dom.storage_access.auto_grants.exclude_third_party_trackers
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Storage-access API.
- name: dom.storage_access.enabled
type: bool
value: true
mirror: always
# Forward-Declared Storage-access API.
- name: dom.storage_access.forward_declared.enabled
type: bool
value: false
mirror: always
# How long the Forward-Declared Storage-access API allows between pair requests
# in seconds
- name: dom.storage_access.forward_declared.lifetime
type: uint32_t
value: 15 * 60
mirror: always
# The maximum number of origins that a given third-party tracker is allowed
# to have concurrent access to before the user is presented with a storage
# access prompt. Only effective when the auto_grants pref is turned on.
- name: dom.storage_access.max_concurrent_auto_grants
type: int32_t
value: 5
mirror: always
- name: dom.storage_access.frame_only
type: bool
value: true
mirror: always
# Only grant storage access to secure contexts.
- name: dom.storage_access.dont_grant_insecure_contexts
type: RelaxedAtomicBool
value: true
mirror: always
# Whether the File System API is enabled
- name: dom.fs.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Whether the WritableFileStream is enabled or disabled.
- name: dom.fs.writable_file_stream.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# A pref that is used to enable testing features.
- name: dom.fs.testing
type: SequentiallyConsistentAtomicBool
value: false
mirror: always
# A pref that is used to slow down database initialization for testing purposes.
- name: dom.fs.databaseInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# LocalStorage data limit as determined by summing up the lengths of all string
# keys and values. This is consistent with the legacy implementation and other
# browser engines. This value should really only ever change in unit testing
# where being able to lower it makes it easier for us to test certain edge
# cases. Measured in KiBs.
- name: dom.storage.default_quota
type: RelaxedAtomicUint32
# Only allow relatively small amounts of data since performance of the
# synchronous IO is very bad. We are enforcing simple per-origin quota only.
value: 5 * 1024
mirror: always
# Per-site quota for legacy LocalStorage implementation.
- name: dom.storage.default_site_quota
type: RelaxedAtomicUint32
value: 25 * 1024
mirror: always
# Whether or not the unsupported legacy implemenation should be enabled. Please
# don't advertise this pref as a way for disabling LSNG. This pref is intended
# for internal testing only and will be removed in near future. Accidental
# disabling of LSNG can lead to a data loss in a combination with disabled
# shadow writes. Disabling of shadow writes is the initial step towards
# removing legacy implementation and will be done soon.
- name: dom.storage.enable_unsupported_legacy_implementation
type: RelaxedAtomicBool
value: false
mirror: always
do_not_use_directly: true
# Whether the migration from unsupported legacy implementation is enabled.
- name: dom.storage.enable_migration_from_unsupported_legacy_implementation
type: RelaxedAtomicBool
value: false
mirror: always
# The amount of snapshot peak usage which is attempted to be pre-incremented
# during snapshot creation.
- name: dom.storage.snapshot_peak_usage.initial_preincrement
type: RelaxedAtomicUint32
value: 16384
mirror: always
# The amount of snapshot peak usage which is attempted to be pre-incremented
# during snapshot creation if the LocalStorage usage was already close to the
# limit (a fallback for dom.storage.snapshot_peak_usage.initial_preincrement).
- name: dom.storage.snapshot_peak_usage.reduced_initial_preincrement
type: RelaxedAtomicUint32
value: 4096
mirror: always
# The amount of snapshot peak usage which is attempted to be pre-incremented
# beyond the specific values which are subsequently requested after snapshot
# creation.
- name: dom.storage.snapshot_peak_usage.gradual_preincrement
type: RelaxedAtomicUint32
value: 4096
mirror: always
# The amount of snapshot peak usage which is attempted to be pre-incremented
# beyond the specific values which are subsequently requested after snapshot
# creation if the LocalStorage total usage was already close to the limit
# (a fallback for dom.storage.snapshot_peak_usage.gradual_preincrement).
- name: dom.storage.snapshot_peak_usage.reduced_gradual_preincrement
type: RelaxedAtomicUint32
value: 1024
mirror: always
# How long between a snapshot becomes idle and when we actually finish the
# snapshot. This preference is only used when "dom.storage.snapshot_reusing"
# is true.
- name: dom.storage.snapshot_idle_timeout_ms
type: uint32_t
value: 5000
mirror: always
# Is support for Storage test APIs enabled?
- name: dom.storage.testing
type: SequentiallyConsistentAtomicBool
value: false
mirror: always
# A pref that is used to slow down database initialization for testing purposes.
- name: dom.storage.databaseInitialization.pauseOnIOThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# A pref that is used to slow down request finalization for testing purposes.
- name: dom.storage.requestFinalization.pauseOnDOMFileThreadMs
type: RelaxedAtomicUint32
value: 0
mirror: always
# This enables the SVGPathSegment APIs
- name: dom.svg.pathSegment.enabled
type: bool
value: true
mirror: always
# For area and anchor elements with target=_blank and no rel set to
# opener/noopener.
- name: dom.targetBlankNoOpener.enabled
type: bool
value: true
mirror: always
# Is support for Selection.GetRangesForInterval enabled?
- name: dom.testing.selection.GetRangesForInterval
type: bool
value: false
mirror: always
- name: dom.testing.structuredclonetester.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# To enable TestUtils interface on WPT
- name: dom.testing.testutils.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.hidden_until_found.enabled
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
- name: dom.text_fragments.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
- name: dom.text_fragments.create_text_fragment.enabled
type: bool
value: false
mirror: always
- name: dom.text_fragments.create_text_fragment.timeout_seconds
type: uint32_t
value: 5
mirror: always
- name: dom.textMetrics.actualBoundingBox.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.textMetrics.baselines.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.textMetrics.emHeight.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.textMetrics.fontBoundingBox.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Time (in ms) that it takes to regenerate 1ms.
- name: dom.timeout.background_budget_regeneration_rate
type: RelaxedAtomicInt32
value: 100
mirror: always
# Time (in ms) that it takes to regenerate 1ms.
- name: dom.timeout.foreground_budget_regeneration_rate
type: RelaxedAtomicInt32
value: 1
mirror: always
# Maximum value (in ms) for the background budget. Only valid for
# values greater than 0.
- name: dom.timeout.background_throttling_max_budget
type: RelaxedAtomicInt32
value: 50
mirror: always
# Maximum value (in ms) for the foreground budget. Only valid for
# values greater than 0.
- name: dom.timeout.foreground_throttling_max_budget
type: RelaxedAtomicInt32
value: -1
mirror: always
# The maximum amount a timeout can be delayed by budget throttling.
- name: dom.timeout.budget_throttling_max_delay
type: RelaxedAtomicInt32
value: 15000
mirror: always
# Turn on budget throttling by default.
- name: dom.timeout.enable_budget_timer_throttling
type: RelaxedAtomicBool
value: true
mirror: always
# Should we defer timeouts and intervals while loading a page. Released
# on Idle or when the page is loaded.
# A URI list in dom.timeout.defer_during_load.force-disable can override this
# and disable this optimization for a site.
- name: dom.timeout.defer_during_load
type: bool
value: true
mirror: always
# Sites we shouldn't defer timeouts and intervals while loading a page.
# comma-separated list, see IsURIInPrefList() for format details
- name: dom.timeout.defer_during_load.force-disable
type: String
value: >-
*.usps.com,
*.nvidia.com,
*.fedex.com,
*.msci.com
mirror: never
# Maximum amount of time in milliseconds consecutive setTimeout()/setInterval()
# callback are allowed to run before yielding the event loop.
- name: dom.timeout.max_consecutive_callbacks_ms
type: RelaxedAtomicUint32
value: 4
mirror: always
# Maximum deferral time for setTimeout/Interval in milliseconds
- name: dom.timeout.max_idle_defer_ms
type: uint32_t
value: 10*1000
mirror: always
# Delay in ms from document load until we start throttling background timeouts.
- name: dom.timeout.throttling_delay
type: RelaxedAtomicInt32
value: 30000
mirror: always
# UDPSocket API
- name: dom.udpsocket.enabled
type: bool
value: false
mirror: always
# Whether to dump worker use counters
- name: dom.use_counters.dump.worker
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to dump document use counters
- name: dom.use_counters.dump.document
type: bool
value: false
mirror: always
# Whether to dump page use counters
- name: dom.use_counters.dump.page
type: bool
value: false
mirror: always
# Time limit, in milliseconds, for user gesture transient activation.
- name: dom.user_activation.transient.timeout
type: uint32_t
value: 5000
mirror: always
# Whether to treat the clicks on scrollbars as user interaction with web content.
- name: dom.user_activation.ignore_scrollbars
type: bool
value: true
mirror: always
# Whether to shim a Components object on untrusted windows.
- name: dom.use_components_shim
type: bool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
- name: dom.vibrator.enabled
type: bool
value: false
mirror: always
- name: dom.vibrator.max_vibrate_ms
type: RelaxedAtomicUint32
value: 10000
mirror: always
- name: dom.vibrator.max_vibrate_list_len
type: RelaxedAtomicUint32
value: 128
mirror: always
# Is support for View Transitions Level 1 enabled?
- name: dom.viewTransitions.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Timeout for view transitions.
# TODO(emilio): Figure out the right time-out, Blink uses between 4 and 15
# seconds.
- name: dom.viewTransitions.timeout-ms
type: uint32_t
value: 10000
mirror: always
# Whether view transitions remain active indefinitely. Useful for debugging.
- name: dom.viewTransitions.remain-active
type: bool
value: false
mirror: always
# Whether view transitions use webrender for old-capture
- name: dom.viewTransitions.wr-old-capture
type: bool
value: true
mirror: always
# Whether view transitions use webrender for live-capture
- name: dom.viewTransitions.live-capture
type: bool
value: true
mirror: always
# Is support for WebVR APIs enabled?
# Disabled everywhere, but not removed.
- name: dom.vr.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Should VR sessions always be reported as supported, without first
# checking for VR runtimes? This will prevent permission prompts
# from being suppressed on machines without VR runtimes and cause
# navigator.xr.isSessionSupported to always report that immersive-vr
# is supported.
- name: dom.vr.always_support_vr
type: RelaxedAtomicBool
value: false
mirror: always
# Should AR sessions always be reported as supported, without first
# checking for AR runtimes? This will prevent permission prompts
# from being suppressed on machines without AR runtimes and cause
# navigator.xr.isSessionSupported to always report that immersive-ar
# is supported.
- name: dom.vr.always_support_ar
type: RelaxedAtomicBool
value: false
mirror: always
# It is often desirable to automatically start vr presentation when
# a user puts on the VR headset. This is done by emitting the
# Window.vrdisplayactivate event when the headset's sensors detect it
# being worn. This can result in WebVR content taking over the headset
# when the user is using it outside the browser or inadvertent start of
# presentation due to the high sensitivity of the proximity sensor in some
# headsets, so it is off by default.
- name: dom.vr.autoactivate.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Minimum number of milliseconds that the browser will wait before
# attempting to poll again for connected VR controllers. The browser
# will not attempt to poll for VR controllers until it needs to use them.
- name: dom.vr.controller.enumerate.interval
type: RelaxedAtomicInt32
value: 1000
mirror: always
# The threshold value of trigger inputs for VR controllers.
- name: dom.vr.controller_trigger_threshold
type: AtomicFloat
value: 0.1f
mirror: always
# Minimum number of milliseconds that the browser will wait before
# attempting to poll again for connected VR displays. The browser
# will not attempt to poll for VR displays until it needs to use
# them, such as when detecting a WebVR site.
- name: dom.vr.display.enumerate.interval
type: RelaxedAtomicInt32
value: 5000
mirror: always
# The number of milliseconds since last frame start before triggering a new
# frame. When content is failing to submit frames on time or the lower level
# VR platform APIs are rejecting frames, it determines the rate at which RAF
# callbacks will be called.
- name: dom.vr.display.rafMaxDuration
type: RelaxedAtomicUint32
value: 50
mirror: always
# Minimum number of milliseconds the browser will wait before attempting
# to re-start the VR service after an enumeration returned no devices.
- name: dom.vr.external.notdetected.timeout
type: RelaxedAtomicInt32
value: 60000
mirror: always
# Minimum number of milliseconds the browser will wait before attempting
# to re-start the VR service after a VR API (eg, OpenVR or Oculus)
# requests that we shutdown and unload its libraries.
# To ensure that we don't interfere with VR runtime software auto-updates,
# we will not attempt to re-load the service until this timeout has elapsed.
- name: dom.vr.external.quit.timeout
type: RelaxedAtomicInt32
value: 10000
mirror: always
# Minimum number of milliseconds that the VR session will be kept
# alive after the browser and content no longer are using the
# hardware. If a VR multitasking environment, this should be set
# very low or set to 0.
- name: dom.vr.inactive.timeout
type: RelaxedAtomicInt32
value: 5000
mirror: always
# Maximum number of milliseconds the browser will wait for content to call
# VRDisplay.requestPresent after emitting vrdisplayactivate during VR
# link traversal. This prevents a long running event handler for
# vrdisplayactivate from later calling VRDisplay.requestPresent, which would
# result in a non-responsive browser in the VR headset.
- name: dom.vr.navigation.timeout
type: RelaxedAtomicInt32
value: 5000
mirror: always
# Oculus device
- name: dom.vr.oculus.enabled
type: RelaxedAtomicBool
#if defined(HAVE_64BIT_BUILD) && !defined(ANDROID)
value: true
#else
# On Android, this pref is irrelevant.
value: false
#endif
mirror: always
# When enabled, Oculus sessions may be created with the ovrInit_Invisible
# flag if a page is using tracking but not presenting. When a page
# begins presenting VR frames, the session will be re-initialized without
# the flag. This eliminates the "Firefox not responding" warnings in
# the headset, but might not be compatible with all versions of the Oculus
# runtime.
- name: dom.vr.oculus.invisible.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Minimum number of milliseconds after content has stopped VR presentation
# before the Oculus session is re-initialized to an invisible / tracking
# only mode. If this value is too high, users will need to wait longer
# after stopping WebVR presentation before automatically returning to the
# Oculus home interface. (They can immediately return to the Oculus Home
# interface through the Oculus HUD without waiting this duration)
# If this value is too low, the Oculus Home interface may be visible
# momentarily during VR link navigation.
- name: dom.vr.oculus.present.timeout
type: RelaxedAtomicInt32
value: 500
mirror: always
# OpenVR device
- name: dom.vr.openvr.enabled
type: RelaxedAtomicBool
#if !defined(HAVE_64BIT_BUILD) && !defined(ANDROID)
value: false
#elif defined(XP_WIN) || defined(XP_MACOSX)
# We enable OpenVR by default for Windows and macOS.
value: true
#else
value: false
#endif
mirror: always
# OSVR device
- name: dom.vr.osvr.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Pose prediction reduces latency effects by returning future predicted HMD
# poses to callers of the WebVR API. This currently only has an effect for
# Oculus Rift on SDK 0.8 or greater.
- name: dom.vr.poseprediction.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Enable a separate process for VR module.
- name: dom.vr.process.enabled
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
- name: dom.vr.process.startup_timeout_ms
type: int32_t
value: 5000
mirror: once
# Puppet device, used for simulating VR hardware within tests and dev tools.
- name: dom.vr.puppet.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Starting VR presentation is only allowed within a user gesture or event such
# as VRDisplayActivate triggered by the system. dom.vr.require-gesture allows
# this requirement to be disabled for special cases such as during automated
# tests or in a headless kiosk system.
- name: dom.vr.require-gesture
type: RelaxedAtomicBool
value: true
mirror: always
# Is support for WebXR APIs enabled?
- name: dom.vr.webxr.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Points in the native bounds geometry are required to be quantized
# sufficiently to prevent fingerprinting. The WebXR spec suggests
# quantizing to the nearest 5 centimeters.
- name: dom.vr.webxr.quantization
type: AtomicFloat
value: 0.05f
mirror: always
#ifdef XP_WIN
# Control firing WidgetMouseEvent by handling Windows pointer messages or
# mouse messages.
- name: dom.w3c_pointer_events.dispatch_by_pointer_messages
type: bool
value: true
mirror: always
# Control consuming WM_POINTER for touch pointers instead of WM_TOUCH
- name: dom.w3c_pointer_events.dispatch_by_pointer_messages.touch
type: bool
value: false
mirror: always
# Control whether to fire WidgetTouchEvent from pen pointers for APZ to handle scrolling.
- name: dom.w3c_pointer_events.scroll_by_pen.enabled
type: bool
value: true
mirror: always
#endif
# If the value is >= 0, it will be used for max touch points in child processes.
- name: dom.maxtouchpoints.testing.value
type: int32_t
value: -1
mirror: always
# Maximum value of navigator.hardwareConcurrency.
- name: dom.maxHardwareConcurrency
type: RelaxedAtomicUint32
value: 128
mirror: always
# W3C pointer events draft.
- name: dom.w3c_pointer_events.implicit_capture
type: bool
value: true
mirror: always
- name: dom.w3c_pointer_events.getcoalescedevents_only_in_securecontext
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
# In case Touch API is enabled, this pref controls whether to support
# ontouch* event handlers, document.createTouch, document.createTouchList and
# document.createEvent("TouchEvent").
- name: dom.w3c_touch_events.legacy_apis.enabled
type: bool
value: @IS_ANDROID@
mirror: always
# W3C touch events
# 0 - disabled, 1 - enabled, 2 - autodetect
# Autodetection is currently only supported on Windows and GTK3 (and assumed on
# Android).
- name: dom.w3c_touch_events.enabled
type: int32_t
#if defined(XP_MACOSX)
value: 0
#else
value: 2
#endif
mirror: always
# Is support for the Web Audio API enabled?
- name: dom.webaudio.enabled
type: bool
value: true
mirror: always
- name: dom.webkitBlink.dirPicker.enabled
type: RelaxedAtomicBool
value: @IS_NOT_MOBILE@
mirror: always
# Whether allowing selection across the boundary
# between shadow DOM and light DOM.
- name: dom.shadowdom.selection_across_boundary.enabled
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Mimic Chrome's window.getSelection().toString() behaviour
- name: dom.selection.mimic_chrome_tostring.enabled
type: bool
value: true
mirror: always
# When this pref is enabled:
# - Shadow DOM is not pierced by default anymore
# - The method accepts optional CaretPositionFromPointOptions to allow piercing
# certain ShadowRoots
#
- name: dom.shadowdom.new_caretPositionFromPoint_behavior.enabled
type: bool
value: @IS_NIGHTLY_BUILD@
mirror: always
# NOTE: This preference is used in unit tests. If it is removed or its default
# value changes, please update test_sharedMap_static_prefs.js accordingly.
- name: dom.webcomponents.shadowdom.report_usage
type: bool
value: false
mirror: always
# Is support for Declarative ShadowDOM enabled?
- name: dom.webcomponents.shadowdom.declarative.enabled
type: bool
value: true
mirror: always
# Is the constructed flag error check disabled during adoptedStyleSheets setter?
- name: dom.webcomponents.lift-adoptedstylesheets-restriction.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Is support for the Web GPU API enabled?
- name: dom.webgpu.enabled
type: RelaxedAtomicBool
value: @IS_EARLY_BETA_OR_EARLIER@
mirror: always
# Is support for the Web GPU API enabled on DOM workers?
- name: dom.webgpu.workers.enabled
type: RelaxedAtomicBool
value: @IS_EARLY_BETA_OR_EARLIER@
mirror: always
# Comma-separated list of wgpu backend names to permit in WebGPU adapters.
#
# If non-empty, this is parsed by `wgpu_core::instance::parse_backends_from_comma_list` to
# produce a `wgpu_types::Backends` bitset used to create a `wgpu_core::hub::Global`. As of
# 2023-3-22, recognized names are:
#
# "vulkan" | "vk" => Backends::VULKAN,
# "dx12" | "d3d12" => Backends::DX12,
# "dx11" | "d3d11" => Backends::DX11,
# "metal" | "mtl" => Backends::METAL,
# "opengl" | "gles" | "gl" => Backends::GL,
# "webgpu" => Backends::BROWSER_WEBGPU,
- name: dom.webgpu.wgpu-backend
type: DataMutexString
value: ""
mirror: always
rust: true
- name: dom.webgpu.allow-present-without-readback
type: RelaxedAtomicBool
#if defined(XP_WIN) || defined(XP_MACOSX) || defined(XP_LINUX) && !defined(ANDROID)
value: true
#else
value: false
#endif
mirror: always
# For testing purposes, crash if we don't get a hardware adapter.
- name: dom.webgpu.testing.assert-hardware-adapter
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether to pass labels to the hardware abstraction layer. This is only useful when
# inspecting a WebGPU workload in a GPU debugging tool like renderdoc. Enabling it
# exposes poorly tested driver API surfaces so it should not be enabled by default.
- name: dom.webgpu.hal-labels
type: bool
value: false
mirror: once
rust: true
# Is support for HTMLInputElement.webkitEntries enabled?
- name: dom.webkitBlink.filesystem.enabled
type: bool
value: @IS_NOT_MOBILE@
mirror: always
# Whether the WebMIDI API is enabled
- name: dom.webmidi.enabled
type: bool
value: @IS_NOT_MOBILE@
mirror: always
# midi permission is addon-gated
- name: dom.webmidi.gated
type: bool
value: true
mirror: always
- name: dom.webnotifications.allowcrossoriginiframe
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.webnotifications.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.webnotifications.privateBrowsing.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.webnotifications.requireuserinteraction
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.webnotifications.requireinteraction.enabled
type: RelaxedAtomicBool
#if defined(XP_WIN) || defined(XP_LINUX)
value: true
#else
value: @IS_NIGHTLY_BUILD@
#endif
mirror: always
- name: dom.webnotifications.silent.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.webnotifications.vibrate.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: dom.webnotifications.actions.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Setting log level for notification modules.
# The value follows the enum ConsoleLogLevel in ConsoleInstance.webidl.
- name: dom.webnotifications.loglevel
type: String
value: Error
mirror: never
# Allow notificationclick to open window only during the limited timeframe.
- name: dom.webnotifications.disable_open_click_delay
type: RelaxedAtomicUint32
#if defined(ANDROID)
# Allow service workers to open windows for a longer period after a notification
value: 5000
#else
value: 1000
#endif
mirror: always
- name: dom.worker.canceling.timeoutMilliseconds
type: RelaxedAtomicUint32
value: 30000 # 30 seconds
mirror: always
# Enables the dispatching of console log events from worker threads to the
# main-thread.
- name: dom.worker.console.dispatch_events_to_main_thread
type: RelaxedAtomicBool
value: true
mirror: always
- name: dom.workers.testing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# WebIDL test prefs.
- name: dom.webidl.test1
type: bool
value: true
mirror: always
- name: dom.webidl.test2
type: bool
value: true
mirror: always
# WebShare API - exposes navigator.share()
- name: dom.webshare.enabled
type: bool
#ifdef XP_WIN
value: @IS_EARLY_BETA_OR_EARLIER@
#else
value: false
#endif
mirror: always
# WebShare API - allows WebShare without user interaction (for tests only).
- name: dom.webshare.requireinteraction
type: bool
value: true
mirror: always
# Hide the confirm dialog when a POST request is reloaded.
- name: dom.confirm_repost.testing.always_accept
type: bool
value: false
mirror: always
# Whether we should suspend inactive tabs or not
- name: dom.suspend_inactive.enabled
type: bool
value: @IS_ANDROID@
mirror: always
# The following three prefs control the maximum script run time before slow
# script warning.
# Controls the time that a content script can run before showing a
# notification.
- name: dom.max_script_run_time
type: int32_t
value: 10
mirror: always
# Controls whether we want to wait for user input before surfacing notifying
# the parent process about a long-running script.
- name: dom.max_script_run_time.require_critical_input
type: bool
# On desktop, we don't want to annoy the user with a notification if they're
# not interacting with the browser. On Android however, we automatically
# terminate long-running scripts, so we want to make sure we don't get in the
# way of that by waiting for input.
#if defined(MOZ_WIDGET_ANDROID)
value: false
#else
value: true
#endif
mirror: always
# Controls if a content script will be aborted on child process shutdown.
- name: dom.abort_script_on_child_shutdown
type: bool
value: true
mirror: always
- name: dom.max_chrome_script_run_time
type: int32_t
value: 0
mirror: always
- name: dom.max_ext_content_script_run_time
type: int32_t
value: 5
mirror: always
# Let Resize Observer report the size of all fragments, and not just the
# first one, as per CSSWG resolution:
- name: dom.resize_observer.support_fragments
type: bool
value: false
mirror: always
# Whether allowing using <tab> to move focus to root elements
- name: dom.disable_tab_focus_to_root_element
type: bool
value: true
mirror: always
# Whether or not the `Origin-Agent-Cluster` HTTP header is enabled.
- name: dom.origin_agent_cluster.enabled
type: bool
value: true
mirror: always
# Whether or not agent clusters are origin-keyed by default, blocking the use of
# `document.domain`.
- name: dom.origin_agent_cluster.default
type: bool
value: false
mirror: always
# Whether to make the document name getter follow the spec.
- name: dom.document.name_getter_follow_spec.enabled
type: bool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "editor"
#---------------------------------------------------------------------------
# Default background color of HTML editor. This is referred only when
# "editor.use_custom_colors" is set to `true`.
- name: editor.background_color
type: String
value: "#FFFFFF"
mirror: never
# Delay to mask last input character in password fields.
# If negative value, to use platform's default behavior.
# If 0, no delay to mask password.
# Otherwise, password fields unmask last input character(s) during specified
# time (in milliseconds).
- name: editor.password.mask_delay
type: int32_t
value: -1
mirror: always
# Set to true when you test mask_delay of password editor. If this is set
# to true, "MozLastInputMasked" is fired when last input characters are
# masked by timeout.
- name: editor.password.testing.mask_delay
type: bool
value: false
mirror: always
# How line breakers are treated in single line editor:
# * 0: Only remove the leading and trailing newlines.
# * 1: Remove the first newline and all characters following it.
# * 2: Replace newlines with spaces (default of Firefox).
# * 3: Remove newlines from the string.
# * 4: Replace newlines with commas (default of Thunderbird).
# * 5: Collapse newlines and surrounding white space characters and
# remove them from the string.
# Other values are treated as 1.
- name: editor.singleLine.pasteNewlines
type: int32_t
value: 2
mirror: always
# Whether user pastes should be truncated.
- name: editor.truncate_user_pastes
type: bool
value: true
mirror: always
# When this is set to `true`, "editor.background_color" must be set, then,
# the value is treated as default background color of the HTML editor.
# If `false` and "browser.display.use_system_colors" is set to `true`,
# "browser.display.background_color" is used instead.
# Otherwise, no color is used as default background color.
# This pref is for Thunderbird and SeaMonkey.
- name: editor.use_custom_colors
type: bool
value: false
mirror: always
# If this is set to `true`, CSS mode of style editor is enabled by default
# unless it's a mail editor.
# This pref is for Thunderbird and SeaMonkey.
- name: editor.use_css
type: bool
value: false
mirror: always
# Whether enabling blink compatible white-space normalizer or keep using
# Gecko's traditional white-space normalizer.
- name: editor.white_space_normalization.blink_compatible
type: bool
value: true
mirror: always
# General prefs for editor, indicating whether Gecko-specific editing UI is
# enabled by default. Those UIs are not implemented by any other browsers. So,
# only Firefox users can change some styles with them. This means that Firefox
# users may get unexpected result of some web apps if they assume that users
# cannot change such styles.
- name: editor.resizing.enabled_by_default
type: bool
value: false
mirror: always
- name: editor.inline_table_editing.enabled_by_default
type: bool
value: false
mirror: always
- name: editor.positioning.enabled_by_default
type: bool
value: false
mirror: always
# Controls if a double click word selection also deletes one adjacent whitespace
# (if feasible). This mimics native behaviour on MacOS.
- name: editor.word_select.delete_space_after_doubleclick_selection
type: bool
#ifdef XP_MACOSX
value: true
#else
value: false
#endif
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "extensions."
#---------------------------------------------------------------------------
# Pref that enforces the use of web_accessible_resources for content loads.
# This behavior is default for MV3. The pref controls this for MV2.
- name: extensions.content_web_accessible.enabled
type: bool
value: false
mirror: always
# Whether the InstallTrigger implementation should be enabled (or hidden and
# none of its methods available).
- name: extensions.InstallTriggerImpl.enabled
type: bool
value: false
mirror: always
# Whether the InstallTrigger implementation should be enabled (or completely
# hidden), separate from InstallTriggerImpl because InstallTrigger is improperly
# used also for UA detection.
- name: extensions.InstallTrigger.enabled
type: bool
value: true
mirror: always
# Whether the background.service_worker in the extension manifest.json file
# is enabled.
# all.js locks the pref to false when MOZ_WEBEXT_WEBIDL_ENABLED is false.
- name: extensions.backgroundServiceWorker.enabled
type: bool
value: false
mirror: once
# Maximum number of misspelled words in a text.
- name: extensions.spellcheck.inline.max-misspellings
type: int32_t
value: 500
mirror: always
# Whether the extensions can register a service worker on its own.
# NOTE: WebExtensions Framework ability to register a background service worker
# is not controlled by this pref, only the extension code ability to use
# navigator.serviceWorker.register is locked behind this pref.
- name: extensions.serviceWorkerRegister.allowed
type: RelaxedAtomicBool
value: false
mirror: always
# When true, content scripts of MV2 extensions can run in blob:-documents without
- name: extensions.script_blob_without_match_origin_as_fallback
type: bool
value: false
mirror: always
# Legacy behavior on filterResponse calls on intercepted sw script requests.
- name: extensions.filterResponseServiceWorkerScript.disabled
type: bool
value: false
mirror: always
# This pref governs whether we run webextensions in a separate process (true)
# or the parent/main process (false)
- name: extensions.webextensions.remote
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to expose the MockExtensionAPI test interface in tests.
# The interface MockExtensionAPI doesn't represent a real extension API,
# it is only available in test and does include a series of cases useful
# to test the API request handling without tying the unit test to a
# specific WebExtensions API.
- name: extensions.webidl-api.expose_mock_interface
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to allow acccess to AddonManager to developer sites for testing
# NOTE: We'd like this to be a "hidden" pref once StaticPrefs supports it.
- name: extensions.webapi.testing
type: RelaxedAtomicBool
value: false
mirror: always
# Automation-only pref to allow AddonManager over insecure protocols.
# NOTE: We'd like this to be a "hidden" pref once StaticPrefs supports it.
- name: extensions.webapi.testing.http
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to expose the AddonManager web API.
- name: extensions.webapi.enabled
type: RelaxedAtomicBool
value: @IS_NOT_ANDROID@
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "fission."
#---------------------------------------------------------------------------
# Whether to enable Fission in new windows by default.
# IMPORTANT: This preference should *never* be checked directly, since any
# session can contain a mix of Fission and non-Fission windows. Instead,
# callers should check whether the relevant nsILoadContext has the
# `useRemoteSubframes` flag set.
# Callers which cannot use `useRemoteSubframes` must use
# `Services.appinfo.fissionAutostart` or `mozilla::FissionAutostart()` to check
# whether fission is enabled by default.
- name: fission.autostart
type: bool
value: @IS_NOT_MOBILE@
mirror: never
# Disable storing the session history in the parent process, and accessing it
# over IPC from the child processes.
- name: fission.disableSessionHistoryInParent
type: bool
value: @IS_ANDROID@
mirror: once
do_not_use_directly: true
# If session history is stored in the parent process, enable bfcache for it.
- name: fission.bfcacheInParent
type: bool
value: true
mirror: always
do_not_use_directly: true
# Allow renaming of processes from Private Windows to the eTLD+1 on nightly
# Setting this pref creates a privacy leak, but helps greatly with
# debugging.
- name: fission.processPrivateWindowSiteNames
type: bool
value: false
mirror: always
# Allow renaming of process names to the eTLD+1 on all versions, NOT
# including processes from Private Windows
# Setting this pref creates a privacy leak, but helps greatly with
# debugging
- name: fission.processSiteNames
type: bool
value: false
mirror: always
# Allow showing of current profile along with process names, NOT
# including processes from Private Windows
# Setting this pref creates a privacy leak, but helps greatly with
# debugging
- name: fission.processProfileName
type: bool
value: false
mirror: always
# The strategy used to control how sites are isolated into separate processes
# when Fisison is enabled. This pref has no effect if Fission is disabled.
# See the `WebContentIsolationStrategy` enum in `ProcessIsolation.cpp`.
- name: fission.webContentIsolationStrategy
type: uint32_t
value: 1
mirror: always
# Time in seconds before a site loaded with the Cross-Origin-Opener-Policy
# header is no longer considered high-value and isolated in the "highValueCOOP"
# configuration.
- name: fission.highValue.coop.expiration
type: uint32_t
value: 2592000 # 30 days (in seconds)
mirror: always
# Time in seconds before a site are considered high-value by the login detection
# service is no longer considered high-value and isolated in the "highValueHasSavedLogin"
# or "highValueIsLoggedIn" configuration.
- name: fission.highValue.login.expiration
type: uint32_t
value: 2592000 # 30 days (in seconds)
mirror: always
# If true, capture login attemp, and add "highValueIsLoggedIn" permission to
# the permission manager no matter whether fission is enabled and
# WebContentIsolationStrateg is set to IsolateHighvalue.
- name: fission.highValue.login.monitor
type: bool
value: @IS_ANDROID@
mirror: always
# If true, do not send blocklisted preference values to the subprocess
- name: fission.omitBlocklistedPrefsInSubprocesses
type: RelaxedAtomicBool
value: true
mirror: always
# If true, crash when a blocklisted preference is accessed in a subprocess
- name: fission.enforceBlocklistedPrefsInSubprocesses
type: RelaxedAtomicBool
#ifdef DEBUG
value: true
#else
value: false
#endif
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "font."
#---------------------------------------------------------------------------
# A value greater than zero enables font size inflation for
# pan-and-zoom UIs, so that the fonts in a block are at least the size
# that, if a block's width is scaled to match the device's width, the
# fonts in the block are big enough that at most the pref value ems of
# text fit in *the width of the device*.
#
# When both this pref and the next are set, the larger inflation is used.
- name: font.size.inflation.emPerLine
type: uint32_t
value: 0
mirror: always
# A value greater than zero enables font size inflation for
# pan-and-zoom UIs, so that if a block's width is scaled to match the
# device's width, the fonts in a block are at least the given font size.
# The value given is in twips, i.e., 1/20 of a point, or 1/1440 of an inch.
#
# When both this pref and the previous are set, the larger inflation is used.
- name: font.size.inflation.minTwips
type: uint32_t
value: 0
mirror: always
# In products with multi-mode pan-and-zoom and non-pan-and-zoom UIs,
# this pref forces font inflation to always be enabled in all modes.
# That is, any heuristics used to detect pan-and-zoom
# vs. non-pan-and-zoom modes are disabled and all content is treated
# as pan-and-zoom mode wrt font inflation.
#
# This pref has no effect if font inflation is not enabled through
# either of the prefs above. It has no meaning in single-mode UIs.
- name: font.size.inflation.forceEnabled
type: bool
value: false
mirror: always
# In products with multi-mode pan-and-zoom and non-pan-and-zoom UIs,
# this pref disables font inflation in master-process contexts where
# existing heuristics can't be used determine enabled-ness.
#
# This pref has no effect if font inflation is not enabled through
# either of the prefs above. The "forceEnabled" pref above overrides
# this pref.
- name: font.size.inflation.disabledInMasterProcess
type: bool
value: false
mirror: always
# Defines the font size inflation mapping intercept parameter.
#
# Font size inflation computes a minimum font size, m, based on
# other preferences (see font.size.inflation.minTwips and
# font.size.inflation.emPerLine, above) and the width of the
# frame in which the text resides. Using this minimum, a specified
# font size, s, is mapped to an inflated font size, i, using an
# equation that varies depending on the value of the font size
# inflation mapping intercept parameter, P.
#
# If the intercept parameter is negative, then the following mapping
# function is used:
#
# i = m + s
#
# If the intercept parameter is non-negative, then the mapping function
# is a function such that its graph meets the graph of i = s at the
# point where both i and s are (1 + P/2) * m for values of s that are
# large enough. This means that when s=0, i is always equal to m.
- name: font.size.inflation.mappingIntercept
type: int32_t
value: 1
mirror: always
# Since the goal of font size inflation is to avoid having to
# repeatedly scroll side to side to read a block of text, and there are
# a number of page layouts where a relatively small chunk of text is
# better off not being inflated according to the same algorithm we use
# for larger chunks of text, we want a threshold for an amount of text
# that triggers font size inflation. This preference controls that
# threshold.
#
# It controls the threshold used within an *approximation* of the
# number of lines of text we use. In particular, if we assume that
# each character (collapsing collapsible whitespace) has a width the
# same as the em-size of the font (when, normally, it's actually quite
# a bit smaller on average), this preference gives the percentage of a
# number of lines of text we'd need to trigger inflation. This means
# that a percentage of 100 means that we'd need a number of characters
# (we know the font size and the width) equivalent to one line of
# square text (which is actually a lot less than a real line of text).
#
# A value of 0 means there's no character length threshold.
- name: font.size.inflation.lineThreshold
type: uint32_t
value: 400
mirror: always
# This controls the percentage that fonts will be inflated, if font
# size inflation is enabled. Essentially, if we have a specified font
# size, s, and an inflated font size, i, this specifies that the ratio
# i/s * 100 should never exceed the value of this preference. In order
# for this preference to have any effect, its value must be greater
# than 100, since font inflation can never decrease the ratio i/s.
- name: font.size.inflation.maxRatio
type: uint32_t
value: 0
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "full-screen-api."
#---------------------------------------------------------------------------
- name: full-screen-api.enabled
type: bool
value: true
mirror: always
- name: full-screen-api.allow-trusted-requests-only
type: bool
value: true
mirror: always
- name: full-screen-api.mouse-event-allow-left-button-only
type: bool
value: true
mirror: always
- name: full-screen-api.exit-on.windowOpen
type: bool
value: true
mirror: always
- name: full-screen-api.exit-on.windowRaise
type: bool
value: true
mirror: always
- name: full-screen-api.pointer-lock.enabled
type: bool
value: true
mirror: always
# whether to prevent the top level widget from going fullscreen
- name: full-screen-api.ignore-widgets
type: bool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "fuzzing.". It's important that these can only be
# checked in fuzzing builds (when FUZZING is defined), otherwise you could
# enable the fuzzing stuff on your regular build which would be bad :)
#---------------------------------------------------------------------------
#ifdef FUZZING
- name: fuzzing.enabled
type: bool
#ifdef FUZZING_SNAPSHOT
value: true
#else
value: false
#endif
mirror: always
- name: fuzzing.necko.enabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: fuzzing.necko.http3
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
#ifdef FUZZING_SNAPSHOT
- name: fuzzing.snapshot.enabled
type: RelaxedAtomicBool
value: true
mirror: always
#endif
# This configures a virtual authenticator for WebAuthn. The value encodes the
# arguments to the WebDriver "Add Virtual Authenticator" extension command.
# Bits 0, 1, 2, and 3 encode "is_user_verified", "is_user_consenting",
# "has_user_verification", and "has_resident_key" in that order. Bit 5 encodes
# the transport, either "usb" (0) or "internal" (1). Bits 6 and 7 encode the
# protocol, either "ctap1/u2f" (1), "ctap2" (2), or "ctap2_1" (3). Note that
# the valid protocol values are non-zero---an authenticator will not be
# configured if this pref is set to zero. Changing this pref requires
# a restart.
- name: fuzzing.webauthn.authenticator_config
type: RelaxedAtomicUint32
value: 0
mirror: always
rust: true
#endif
#---------------------------------------------------------------------------
# Prefs starting with "general."
#---------------------------------------------------------------------------
- name: general.aboutConfig.enable
type: bool
value: true
mirror: always
# Limits the depth of recursive conversion of data when opening
# a content to view. This is mostly intended to prevent infinite
# loops with faulty converters involved.
- name: general.document_open_conversion_depth_limit
type: uint32_t
value: 20
mirror: always
- name: general.smoothScroll
type: RelaxedAtomicBool
value: true
mirror: always
# This pref and general.smoothScroll.stopDecelerationWeighting determine
# the timing function.
- name: general.smoothScroll.currentVelocityWeighting
type: AtomicFloat
value: 0.25
mirror: always
# To connect consecutive scroll events into a continuous flow, the animation's
# duration should be longer than scroll events intervals (or else the scroll
# will stop before the next event arrives - we're guessing the next interval
# by averaging recent intervals).
# This defines how much longer the duration is compared to the events
# interval (percentage).
- name: general.smoothScroll.durationToIntervalRatio
type: RelaxedAtomicInt32
value: 200
mirror: always
- name: general.smoothScroll.lines
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.lines.durationMaxMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.lines.durationMinMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.mouseWheel
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.mouseWheel.durationMaxMS
type: RelaxedAtomicInt32
value: 200
mirror: always
- name: general.smoothScroll.mouseWheel.durationMinMS
type: RelaxedAtomicInt32
value: 50
mirror: always
- name: general.smoothScroll.other
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.other.durationMaxMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.other.durationMinMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.pages
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.pages.durationMaxMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.pages.durationMinMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.scrollbars
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.scrollbars.durationMaxMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.scrollbars.durationMinMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.pixels
type: RelaxedAtomicBool
value: true
mirror: always
- name: general.smoothScroll.pixels.durationMaxMS
type: RelaxedAtomicInt32
value: 150
mirror: always
- name: general.smoothScroll.pixels.durationMinMS
type: RelaxedAtomicInt32
value: 150
mirror: always
# This pref and general.smoothScroll.currentVelocityWeighting determine
# the timing function.
- name: general.smoothScroll.stopDecelerationWeighting
type: AtomicFloat
value: 0.4f
mirror: always
# Alternative smooth scroll physics. ("MSD" = Mass-Spring-Damper)
- name: general.smoothScroll.msdPhysics.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
- name: general.smoothScroll.msdPhysics.continuousMotionMaxDeltaMS
type: RelaxedAtomicInt32
value: 120
mirror: always
- name: general.smoothScroll.msdPhysics.motionBeginSpringConstant
type: RelaxedAtomicInt32
value: 1250
mirror: always
- name: general.smoothScroll.msdPhysics.slowdownMinDeltaMS
type: RelaxedAtomicInt32
value: 12
mirror: always
- name: general.smoothScroll.msdPhysics.slowdownMinDeltaRatio
type: AtomicFloat
value: 1.3f
mirror: always
- name: general.smoothScroll.msdPhysics.slowdownSpringConstant
type: RelaxedAtomicInt32
value: 2000
mirror: always
- name: general.smoothScroll.msdPhysics.regularSpringConstant
type: RelaxedAtomicInt32
value: 1000
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "geo."
#---------------------------------------------------------------------------
# Is support for Navigator.geolocation enabled?
- name: geo.enabled
type: bool
value: true
mirror: always
# Time, in milliseconds, to wait for the location provider to spin up.
- name: geo.timeout
type: int32_t
value: 6000
mirror: always
#ifdef MOZ_ENABLE_DBUS
# Whether to use Geoclue location provider (if available on the system).
- name: geo.provider.use_geoclue
type: bool
value: true
mirror: always
# Whether to always provide high location accuracy, even if site
# doesn't actually request this level of accuracy.
# Almost no site correctly requests high accuracy so force it by default
# for compatibility with other geolocation providers.
- name: geo.provider.geoclue.always_high_accuracy
type: bool
value: true
mirror: always
# Time in milliseconds after which geoclue will try to fallback to MLS if no
# location is received after successful start.
- name: geo.provider.geoclue.mls_fallback_timeout_ms
type: uint32_t
value: 5000
mirror: always
#endif
# If true, open system preferences for the user when geolocation is requested
# by the user but OS geolocation permission is not available.
- name: geo.prompt.open_system_prefs
type: bool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "gfx."
#---------------------------------------------------------------------------
# Allow 24-bit colour when the hardware supports it.
- name: gfx.android.rgb16.force
type: bool
value: false
mirror: once
- name: gfx.apitrace.enabled
type: bool
value: false
mirror: once
- name: gfx.blithelper.precision
type: RelaxedAtomicUint32
value: 2 # { 0: lowp, 1: mediump, 2: highp }
mirror: always
- name: gfx.blithelper.lut-size.rgb.b
type: RelaxedAtomicUint32
value: 15
mirror: always
- name: gfx.blithelper.lut-size.rgb.g
type: RelaxedAtomicUint32
value: 31
mirror: always
- name: gfx.blithelper.lut-size.rgb.r
type: RelaxedAtomicUint32
value: 31
mirror: always
- name: gfx.blithelper.lut-size.ycbcr.cb
type: RelaxedAtomicUint32
value: 15
mirror: always
- name: gfx.blithelper.lut-size.ycbcr.cr
type: RelaxedAtomicUint32
value: 31
mirror: always
- name: gfx.blithelper.lut-size.ycbcr.y
type: RelaxedAtomicUint32
value: 31
mirror: always
# Nb: we ignore this pref on release and beta.
- name: gfx.blocklist.all
type: int32_t
value: 0
mirror: once
#if defined(XP_DARWIN)
- name: gfx.cairo_quartz_cg_layer.enabled
type: bool
value: true
mirror: always
#endif
- name: gfx.canvas.accelerated
type: bool
#if defined(XP_MACOSX) || defined(XP_LINUX) && !defined(ANDROID)
value: true
#elif defined(MOZ_WIDGET_ANDROID)
value: true
#elif defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: always
# Whether to attempt to enable Accelerated Canvas2D regardless of blocklisting.
- name: gfx.canvas.accelerated.force-enabled
type: bool
value: false
mirror: always
- name: gfx.canvas.accelerated.async-present
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.canvas.accelerated.cache-items
type: RelaxedAtomicUint32
value: 8192
mirror: always
- name: gfx.canvas.accelerated.cache-size
type: RelaxedAtomicUint32
value: 256
mirror: always
- name: gfx.canvas.accelerated.reserve-empty-cache
type: RelaxedAtomicUint32
value: 36
mirror: always
- name: gfx.canvas.accelerated.max-draw-target-count
type: RelaxedAtomicUint32
value: 200
mirror: always
- name: gfx.canvas.accelerated.max-size
type: RelaxedAtomicInt32
value: 8192
mirror: always
- name: gfx.canvas.accelerated.min-size
type: RelaxedAtomicInt32
value: 128
mirror: always
- name: gfx.canvas.accelerated.max-surface-size
type: RelaxedAtomicUint32
value: 5280
mirror: always
- name: gfx.canvas.accelerated.shared-page-size
type: RelaxedAtomicUint32
value: 1024
mirror: always
# The minimum number of frames before acting on performance profile info
- name: gfx.canvas.accelerated.profile-frames
type: RelaxedAtomicUint32
value: 10
mirror: always
# The ratio of failed frames to total frames when to fall back from acceleration
- name: gfx.canvas.accelerated.profile-fallback-ratio
type: AtomicFloat
value: 0.3
mirror: always
# The ratio of cache misses at which to fail a profile frame
- name: gfx.canvas.accelerated.profile-cache-miss-ratio
type: AtomicFloat
value: 0.66
mirror: always
# The maximum size of the GPU path cache in MB.
- name: gfx.canvas.accelerated.gpu-path-size
type: RelaxedAtomicUint32
value: 4
mirror: always
# The maximum allowed complexity of a GPU path.
- name: gfx.canvas.accelerated.gpu-path-complexity
type: RelaxedAtomicUint32
value: 4000
mirror: always
# Whether to accelerate stroked paths by converting them to fill paths.
- name: gfx.canvas.accelerated.stroke-to-fill-path
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to use aa-stroke to accelerate stroked paths.
- name: gfx.canvas.accelerated.aa-stroke.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Draws an indicator if acceleration is used.
- name: gfx.canvas.accelerated.debug
type: RelaxedAtomicBool
value: false
mirror: always
# 0x7fff is the maximum supported xlib surface size and is more than enough for canvases.
- name: gfx.canvas.max-size
type: RelaxedAtomicInt32
value: 0x7fff
mirror: always
- name: gfx.canvas.remote
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
- name: gfx.canvas.remote.allow-in-parent
type: bool
value: false
mirror: once
# Whether OffscreenCanvas can use remote canvas
- name: gfx.canvas.remote.allow-offscreen
type: RelaxedAtomicBool
value: true
mirror: always
# How many worker threads spawned for remote canvas
# -1 - Calculate based on processor cores
# 0 - No worker threads spawned, will do work on CanvasRenderThread
# >0 - Create worker thread pool with given size
- name: gfx.canvas.remote.worker-threads
type: int32_t
#if defined(XP_WIN)
value: -1
#else
value: 0
#endif
mirror: once
# Default size of the shmem buffers used for recording
- name: gfx.canvas.remote.default-buffer-size
type: RelaxedAtomicUint32
value: 32 * 1024
mirror: always
# Maximum number of Default size shmem buffers to use
- name: gfx.canvas.remote.max_default_buffers
type: RelaxedAtomicUint32
value: 256
mirror: always
# How many times to spin before waiting in remote canvas
- name: gfx.canvas.remote.max-spin-count
type: RelaxedAtomicUint32
value: 500
mirror: always
# How long to wait in milliseconds for the next event while in a transaction
- name: gfx.canvas.remote.event-timeout-ms
type: RelaxedAtomicUint32
value: 2
mirror: always
# How many times we have a spare buffer before we drop one
- name: gfx.canvas.remote.drop-buffer-limit
type: RelaxedAtomicUint32
value: 100
mirror: always
# Delay in milliseconds to drop buffers when there have been no non-empty transactions
- name: gfx.canvas.remote.drop-buffer-milliseconds
type: RelaxedAtomicUint32
value: 10000
mirror: always
- name: gfx.canvas.remote.use-draw-image-fast-path
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.canvas.remote.use-draw-image-fast-path-d3d
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.canvas.remote.recycle-used-data-surface
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.canvas.remote.use-canvas-translator-event
type: bool
value: true
mirror: once
- name: gfx.color_management.display_profile
type: DataMutexString
value: ""
mirror: always # But be warned: We cache the result.
- name: gfx.color_management.force_srgb
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.color_management.native_srgb
type: RelaxedAtomicBool
#if defined(XP_MACOSX)
value: true
#else
value: false
#endif
mirror: always
- name: gfx.color_management.enablev4
type: RelaxedAtomicBool
value: true
mirror: always
# 0 = Off, 1 = Full, 2 = Tagged Images Only.
# See CMSMode in gfx/thebes/gfxPlatform.h.
- name: gfx.color_management.mode
type: RelaxedAtomicInt32
value: 2
mirror: always
# The zero default here should match QCMS_INTENT_DEFAULT from qcms.h
- name: gfx.color_management.rendering_intent
type: RelaxedAtomicInt32
value: 0
mirror: always
- name: gfx.color_management.rec709_gamma_as_srgb
type: RelaxedAtomicBool
value: true # Tragic backwards compat.
mirror: always
- name: gfx.color_management.rec2020_gamma_as_rec709
type: RelaxedAtomicBool
value: true # Match naive behavior, but hopefully we can stop soon!
mirror: always
# Whether GL contexts can be migrated to a different GPU (to match the one the
# OS is using for composition).
#
# 0 = force disable migration
# 1 = use migration where in safe configurations (the default)
# 2 = force enable migration (for testing)
- name: gfx.compositor.gpu-migration
type: RelaxedAtomicInt32
value: 1
mirror: always
- name: gfx.core-animation.tint-opaque
type: RelaxedAtomicBool
value: false
mirror: always
#ifdef XP_DARWIN
# Create specialized video-only layers for video content in
# fullscreen windows. Consistently works well on Apple Silicon,
# some issues remain on Intel hardware.
- name: gfx.core-animation.specialize-video
type: RelaxedAtomicBool
#if defined(MOZ_AARCH64) && defined(XP_MACOSX)
value: true
#else
value: false
#endif
mirror: always
#endif
#if defined(XP_DARWIN) && defined(NIGHTLY_BUILD)
# Spoof the timing of the video sample instead of marking the untimed
# sample to be displayed immediately.
- name: gfx.core-animation.specialize-video.spoof-timing
type: RelaxedAtomicBool
value: false
mirror: always
# Check that the sample has a color space and if it doesn't, log that
# and supply the default color space from the main display.
- name: gfx.core-animation.specialize-video.check-color-space
type: RelaxedAtomicBool
value: false
mirror: always
# Log properties of the video surface, buffer, and format.
- name: gfx.core-animation.specialize-video.log
type: RelaxedAtomicBool
value: false
mirror: always
#endif
#ifdef XP_DARWIN
- name: gfx.core-animation.low-power-telemetry-frames
type: int32_t
value: 600
mirror: once
#endif
#if defined(MOZ_WIDGET_ANDROID)
# Overrides the glClear color used when the surface origin is not (0, 0)
# Used for drawing a border around the content.
- name: gfx.compositor.override.clear-color.r
type: AtomicFloat
value: 0.0f
mirror: always
- name: gfx.compositor.override.clear-color.g
type: AtomicFloat
value: 0.0f
mirror: always
- name: gfx.compositor.override.clear-color.b
type: AtomicFloat
value: 0.0f
mirror: always
- name: gfx.compositor.override.clear-color.a
type: AtomicFloat
value: 0.0f
mirror: always
#endif # defined(MOZ_WIDGET_ANDROID)
- name: gfx.content.always-paint
type: RelaxedAtomicBool
value: false
mirror: always
# Size in megabytes
- name: gfx.content.skia-font-cache-size
type: int32_t
value: 5
mirror: once
- name: gfx.device-reset.limit
type: int32_t
value: 10
mirror: once
- name: gfx.device-reset.threshold-ms
type: int32_t
value: -1
mirror: once
# Whether to disable the automatic detection and use of direct2d.
- name: gfx.direct2d.disabled
type: bool
value: true
mirror: once
# Whether to attempt to enable Direct2D regardless of automatic detection or
# blacklisting.
- name: gfx.direct2d.force-enabled
type: bool
value: false
mirror: once
- name: gfx.direct2d.target-independent-rasterization.disabled
type: bool
value: false
mirror: once
- name: gfx.direct3d11.reuse-decoder-device
type: bool
value: true
mirror: once
# Enable reuse decoder device even when it is blocked.
- name: gfx.direct3d11.reuse-decoder-device-force-enabled
type: bool
value: false
mirror: once
- name: gfx.direct3d11.allow-keyed-mutex
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.direct3d11.use-double-buffering
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.direct3d11.enable-debug-layer
type: bool
value: false
mirror: once
- name: gfx.direct3d11.break-on-error
type: bool
value: false
mirror: once
- name: gfx.direct3d11.sleep-on-create-device
type: int32_t
value: 0
mirror: once
# Rate by which the frame rate is divided. I.e. at a number higher than 1 we
# will only refresh every <x> frames.
- name: gfx.display.frame-rate-divisor
type: RelaxedAtomicInt32
value: 1
mirror: always
- name: gfx.display.max-frame-rate
type: RelaxedAtomicInt32
value: 0
mirror: always
# Whether to disable downloadable font cache so that behavior is consistently
# the uncached load behavior across pages (useful for testing reflow problems)
- name: gfx.downloadable_fonts.disable_cache
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to preserve color bitmap tables in fonts (bypassing OTS).
# Currently these are supported only on platforms where we use Freetype
# to render fonts (Linux/Gtk and Android).
- name: gfx.downloadable_fonts.keep_color_bitmaps
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to validate OpenType variation tables in fonts.
- name: gfx.downloadable_fonts.validate_variation_tables
type: RelaxedAtomicBool
value: true
mirror: always
# Whether OTS validation should be applied to OpenType Layout (OTL) tables.
- name: gfx.downloadable_fonts.otl_validation
type: RelaxedAtomicBool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
- name: gfx.e10s.font-list.shared
type: bool
value: true
mirror: once
# Do we fire a notification about missing fonts, so the front-end can decide
# whether to try and do something about it (e.g. download additional fonts)?
- name: gfx.missing_fonts.notify
type: RelaxedAtomicBool
value: false
mirror: always
#if !defined(MOZ_WIDGET_ANDROID)
- name: gfx.egl.prefer-gles.enabled
type: bool
#if defined(MOZ_WIDGET_GTK) && defined(MOZ_AARCH64)
value: true
#else
value: false
#endif
mirror: once
#endif
# [Windows] Whether registry FontSubstitutes entries are used unconditionally,
# or only if the original font is not available.
#if defined(XP_WIN)
- name: gfx.windows-font-substitutes.always
type: bool
value: false
mirror: once
#endif
- name: gfx.font-list-omt.enabled
type: bool
#if defined(XP_MACOSX)
value: true
#else
value: false
#endif
mirror: once
# [Android] OPPO, realme and OnePlus device seem to crash when using Font
# Match API. We turn off this feature on these devices. Set true if you want to
# turn on it at force.
#if defined(MOZ_WIDGET_ANDROID)
- name: gfx.font-list.use_font_match_api.force-enabled
type: bool
value: false
mirror: once
#endif
# Whether to load fonts (e.g. Twemoji Mozilla) bundled with the application:
# -1 - Auto behavior based on OS version (currently, disables loading on
# "low-memory" Android devices)
# 0 - Skip loading any bundled fonts
# 1 - Always load bundled fonts
- name: gfx.bundled-fonts.activate
type: int32_t
value: -1
mirror: once
- name: gfx.font_loader.delay
type: RelaxedAtomicUint32
#if defined(XP_WIN)
value: 60000
#else
value: 8000
#endif
mirror: always
# Disable antialiasing of Ahem, for use in tests.
- name: gfx.font_rendering.ahem_antialias_none
type: RelaxedAtomicBool
value: false
mirror: always
#if defined(XP_DARWIN)
# Set to true to revert from HarfBuzz AAT shaping to the old Core Text
# backend.
- name: gfx.font_rendering.coretext.enabled
type: RelaxedAtomicBool
value: false
mirror: always
#endif
- name: gfx.font_rendering.colr_v1.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.font_rendering.opentype_svg.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
- name: gfx.font_rendering.fallback.async
type: RelaxedAtomicBool
value: true
mirror: always
# whether to always search all font cmaps during system font fallback
- name: gfx.font_rendering.fallback.always_use_cmaps
type: RelaxedAtomicBool
value: false
mirror: always
# whether to do font fallback for codepoints with General Category = Unassigned
- name: gfx.font_rendering.fallback.unassigned_chars
type: RelaxedAtomicBool
value: false
mirror: always
#ifdef MOZ_WIDGET_GTK
- name: gfx.font_rendering.fontconfig.max_generic_substitutions
type: RelaxedAtomicUint32
value: 3
mirror: always
#endif
#if defined(XP_WIN)
# Whether the DirectWrite bold simulation should be used when a bold font-weight
# is requested but no bold face available in the family. This renders poorly with
# some third-party fonts, so by default we disable it for webfonts and allow it
# only with locally-installed fonts.
# Values:
# 0 - never use DWrite bold simulation; always multi-strike instead
# 1 - use DWrite bold for installed fonts, multi-strike for webfont resources
# 2 - use DWrite bold for all fonts
- name: gfx.font_rendering.directwrite.bold_simulation
type: RelaxedAtomicUint32
value: 1
mirror: always
#endif
- name: gfx.font_rendering.graphite.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Cache shaped word results
- name: gfx.font_rendering.wordcache.charlimit
type: RelaxedAtomicUint32
value: 32
mirror: always
# Cache shaped word results
- name: gfx.font_rendering.wordcache.maxentries
type: RelaxedAtomicUint32
value: 10000
mirror: always
# The level of logging:
# - 0: no logging;
# - 1: adds errors;
# - 2: adds warnings;
# - 3 or 4: adds debug logging.
# If you set the value to 4, you will also need to set the environment
# variable MOZ_LOG to gfx:4. See mozilla/Logging.h for details.
- name: gfx.logging.level
type: RelaxedAtomicInt32
value: mozilla::gfx::LOG_DEFAULT
mirror: always
include: mozilla/gfx/LoggingConstants.h
- name: gfx.logging.crash.length
type: uint32_t
value: 16
mirror: once
# The maximums here are quite conservative, we can tighten them if problems show up.
- name: gfx.logging.texture-usage.enabled
type: bool
value: false
mirror: once
- name: gfx.logging.peak-texture-usage.enabled
type: bool
value: false
mirror: once
- name: gfx.logging.slow-frames.enabled
type: bool
value: false
mirror: once
# Use gfxPlatform::MaxAllocSize instead of the pref directly.
- name: gfx.max-alloc-size
type: int32_t
value: (int32_t)0x7FFFFFFF
mirror: once
do_not_use_directly: true
# Use gfxPlatform::MaxTextureSize instead of the pref directly.
- name: gfx.max-texture-size
type: int32_t
value: (int32_t)32767
mirror: once
do_not_use_directly: true
- name: gfx.offscreencanvas.shared-provider
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.offscreencanvas.snapshot-timeout-ms
type: int32_t
value: 10000
mirror: always
- name: gfx.omta.background-color
type: bool
value: true
mirror: always
- name: gfx.partialpresent.force
type: RelaxedAtomicInt32
value: 0
mirror: always
# SwapInterval
- name: gfx.swap-interval.glx
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.swap-interval.egl
type: RelaxedAtomicBool
mirror: always
#ifdef MOZ_WIDGET_ANDROID
value: true
#else
value: false
#endif
# Log severe performance warnings to the error console and profiles.
# This should be use to quickly find which slow paths are used by test cases.
- name: gfx.perf-warnings.enabled
type: RelaxedAtomicBool
value: false
mirror: always
#ifdef MOZ_X11
# Whether to force using GLX over EGL.
- name: gfx.x11-egl.force-disabled
type: bool
value: false
mirror: once
# Whether to force using EGL over GLX.
- name: gfx.x11-egl.force-enabled
type: bool
value: false
mirror: once
- name: gfx.x11.glx_sgi_video_sync
type: bool
value: false
mirror: once
#endif
- name: gfx.testing.device-fail
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.testing.device-reset
type: RelaxedAtomicInt32
value: 0
mirror: always
# Meant to be used for tests only. If greater than 0 then we assert that the
# number of active render textures increases by this amount or less.
#ifdef DEBUG
- name: gfx.testing.assert-render-textures-increase
type: RelaxedAtomicInt32
value: 0
mirror: always
#endif
- name: gfx.text.disable-aa
type: bool
value: false
mirror: once
- name: gfx.text.subpixel-position.force-enabled
type: bool
value: false
mirror: once
- name: gfx.text.subpixel-position.force-disabled
type: bool
value: false
mirror: once
- name: gfx.use-iosurface-textures
type: bool
value: false
mirror: once
- name: gfx.use-mutex-on-present
type: bool
value: false
mirror: once
# Use SurfaceTextures as preferred backend for TextureClient/Host.
- name: gfx.use-surfacetexture-textures
type: bool
value: false
mirror: once
- name: gfx.vsync.compositor.unobserve-count
type: int32_t
value: 10
mirror: once
- name: gfx.vsync.force-disable-waitforvblank
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.will-change.ignore-opacity
type: RelaxedAtomicBool
value: true
mirror: always
# Should we override the blocklist to enable WebGPU?
- name: gfx.webgpu.ignore-blocklist
type: bool
value: false
mirror: once
# Whether to use the WebRender hardware backend
- name: gfx.webrender.all
type: bool
value: false
mirror: once
#ifdef XP_WIN
- name: gfx.webrender.force-angle
type: bool
value: true
mirror: once
#endif
# WebRender is not enabled when there is no GPU process on window when
# WebRender uses ANGLE. It is for avoiding that WebGL and WebRender use ANGLE
# at once. But there is a case that we want to enable WebRender for testing.
#ifdef XP_WIN
- name: gfx.webrender.enabled-no-gpu-process-with-angle-win
type: bool
value: true
mirror: once
#endif
- name: gfx.webrender.svg-filter-effects
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.also-convert-css-filters
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.also-use-for-docshell-fecolormatrix
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.opacity
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.toalpha
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.feblend
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.fecolormatrix
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.fecomponenttransfer
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.fecomposite
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.feconvolvematrix
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.fediffuselighting
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.fedisplacementmap
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.fedropshadow
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.feflood
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.fegaussianblur
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.feimage
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.femerge
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.femorphology
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.feoffset
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-filter-effects.fespecularlighting
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.fetile
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-filter-effects.feturbulence
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.svg-images
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.svg-shapes
type: RelaxedAtomicBool
value: true
mirror: always
- name: gfx.webrender.debug.blob.paint-flashing
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.debug.enable-capture
type: bool
value: false
mirror: once
- name: gfx.webrender.debug.dl.dump-parent
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.debug.dl.dump-content
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.debug.dl.dump-content-serialized
type: RelaxedAtomicBool
value: false
mirror: always
# When true, we output warning messages when rejecting surface promotion
# when it has been requested. This is important for color correctness of
# wide color videos, as well as for GPU performance for all videos.
- name: gfx.webrender.debug.surface-promotion-logging
type: RelaxedAtomicBool
value: false
mirror: always
# When true, missing stacking context snapshots will crash the GPU or Parent
# process.
- name: gfx.webrender.debug.missing-snapshot-panic
type: RelaxedAtomicBool
value: false
mirror: always
# When true, missing stacking context snapshots will render as an opaque
# pink image.
- name: gfx.webrender.debug.missing-snapshot-pink
type: RelaxedAtomicBool
value: false
mirror: always
#ifdef MOZ_WIDGET_GTK
- name: gfx.webrender.reject-software-driver
type: bool
value: true
mirror: once
#endif
- name: gfx.webrender.debug.highlight-painted-layers
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.debug.slow-cpu-frame-threshold
type: AtomicFloat
value: 10.0
mirror: always
- name: gfx.webrender.late-scenebuild-threshold
type: RelaxedAtomicInt32
value: 4
mirror: always
- name: gfx.webrender.max-filter-ops-per-chain
type: RelaxedAtomicUint32
value: 64
mirror: always
- name: gfx.webrender.batching.lookback
type: uint32_t
value: 10
mirror: always
- name: gfx.webrender.blob-tile-size
type: uint32_t
value: 256
mirror: always
- name: gfx.webrender.batched-upload-threshold
type: int32_t
#if defined(MOZ_WIDGET_ANDROID)
value: 262144
#else
value: 65536
#endif
mirror: always
- name: gfx.webrender.compositor
type: bool
#if defined(XP_WIN) || defined(XP_DARWIN)
value: true
#else
value: false
#endif
mirror: once
#ifdef NIGHTLY_BUILD
# Keep this pref hidden on non-nightly builds to avoid people accidentally
# turning it on.
- name: gfx.webrender.layer-compositor
type: bool
value: false
mirror: once
#endif
#ifdef XP_WIN
- name: gfx.webrender.layer-compositor-use-composition-surface
type: bool
value: true
mirror: once
#endif
- name: gfx.webrender.scissored-cache-clears.enabled
type: bool
value: true
mirror: once
- name: gfx.webrender.scissored-cache-clears.force-enabled
type: bool
value: false
mirror: once
- name: gfx.webrender.compositor.force-enabled
type: bool
value: false
mirror: once
- name: gfx.webrender.compositor.max_update_rects
type: uint32_t
value: 1
mirror: once
- name: gfx.webrender.compositor.surface-pool-size
type: uint32_t
value: 25
mirror: once
# Number of damage rects we can give to the compositor for a new frame with
# partial present. This controls whether partial present is used or not.
- name: gfx.webrender.max-partial-present-rects
type: uint32_t
#if defined(XP_WIN) || defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GTK)
value: 1
#else
value: 0
#endif
mirror: once
# Whether or not we can reuse the buffer contents using the GL buffer age
# extension, if supported by the platform. This requires partial present
# to be used.
- name: gfx.webrender.allow-partial-present-buffer-age
type: bool
value: true
mirror: once
# Whether or not we should force partial present on.
- name: gfx.webrender.force-partial-present
type: bool
value: false
mirror: once
- name: gfx.webrender.enable-gpu-markers
type: bool
#ifdef DEBUG
value: true
#else
value: false
#endif
mirror: once
- name: gfx.webrender.enable-item-cache
type: bool
value: true
mirror: once
# Whether or not to fallback from WebRender to Software WebRender.
- name: gfx.webrender.fallback.software
type: bool
value: true
mirror: once
#ifdef XP_WIN
# Use IDCompositionFilterEffect to color manage dcomp surfaces.
- name: gfx.webrender.dcomp.color-manage-with-filters
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to use an overlay of hardware decoded video with DirectComposition
- name: gfx.webrender.dcomp-video-hw-overlay-win
type: bool
value: true
mirror: once
# Enable hardware decoded video overlay even when it is blocked.
- name: gfx.webrender.dcomp-video-hw-overlay-win-force-enabled
type: bool
value: false
mirror: once
# Whether to use a yuv video overlay layers with DirectComposition
- name: gfx.webrender.dcomp-video-yuv-overlay-win
type: bool
value: false
mirror: once
- name: gfx.webrender.dcomp-video-vp-scaling-win
type: bool
value: true
mirror: once
# Whether to use virtual surfaces, as opposed to each tile owning a surface.
- name: gfx.webrender.dcomp-use-virtual-surfaces
type: bool
value: true
mirror: once
# Whether to use an overlay of software decoded video with DirectComposition
- name: gfx.webrender.dcomp-video-sw-overlay-win
type: bool
value: true
mirror: once
# Enable software decoded video overlay even when it is blocked.
- name: gfx.webrender.dcomp-video-sw-overlay-win-force-enabled
type: bool
value: false
mirror: once
- name: gfx.webrender.dcomp-video-check-slow-present
type: RelaxedAtomicBool
value: true
mirror: always
# Force triple buffering in overlay's video swap chain
- name: gfx.webrender.dcomp-video-force-triple-buffering
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.webrender.dcomp-video-swap-chain-present-interval-0
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.video.convert-yuv-to-nv12.image-host-win
type: RelaxedAtomicBool
value: true
mirror: always
#endif
# Whether or not fallback to Software WebRender requires the GPU process.
- name: gfx.webrender.fallback.software.requires-gpu-process
type: bool
value: false
mirror: once
- name: gfx.webrender.program-binary-disk
type: bool
#if defined(XP_WIN) || defined(ANDROID)
value: true
#else
value: false
#endif
mirror: once
- name: gfx.webrender.use-optimized-shaders
type: bool
value: true
mirror: once
- name: gfx.webrender.precache-shaders
type: bool
value: false
mirror: once
# When gl debug message is a high severity message, forwward it to gfx critical
# note.
- name: gfx.webrender.gl-debug-message-critical-note
type: bool
#if defined(XP_WIN) && defined(NIGHTLY_BUILD)
value: true
#else
value: false
#endif
mirror: once
# Enable printing gl debug messages
- name: gfx.webrender.gl-debug-message-print
type: bool
value: false
mirror: once
#ifdef NIGHTLY_BUILD
# Keep this pref hidden on non-nightly builds to avoid people accidentally
# turning it on.
- name: gfx.webrender.panic-on-gl-error
type: bool
value: false
mirror: once
#endif
#ifdef XP_WIN
# Enables display of performance debugging counters when DirectComposition
# is used.
# Performance counters are displayed on the top-right corner of the screen.
- name: gfx.webrender.debug.dcomp-counter
type: RelaxedAtomicBool
value: false
mirror: always
# Enables highlighting redraw regions of DCompositionVisual
- name: gfx.webrender.debug.dcomp-redraw-regions
type: RelaxedAtomicBool
value: false
mirror: always
#endif
#ifdef XP_DARWIN
# Files show up in $HOME/Desktop/nativelayerdumps-PID/frame-123.html
- name: gfx.webrender.debug.dump-native-layer-tree-to-file
type: RelaxedAtomicBool
value: false
mirror: always
#endif
- name: gfx.webrender.enable-low-priority-pool
type: RelaxedAtomicBool
#if defined(ANDROID)
value: false
#else
value: true
#endif
mirror: always
# Force subpixel anti-aliasing as much as possible, despite performance cost.
- name: gfx.webrender.quality.force-subpixel-aa-where-possible
type: bool
value: false
mirror: always
- name: gfx.webrender.enable-subpixel-aa
type: bool
mirror: once
#ifdef MOZ_WIDGET_ANDROID
value: false
#else
value: true
#endif
#ifdef XP_MACOSX
- name: gfx.webrender.enable-client-storage
type: bool
value: true
mirror: once
#endif
# Width of WebRender tile size
- name: gfx.webrender.picture-tile-width
type: RelaxedAtomicInt32
value: 1024
mirror: always
# Width of WebRender tile size
- name: gfx.webrender.picture-tile-height
type: RelaxedAtomicInt32
value: 512
mirror: always
# WebRender upper bound for shared surface size
# According to apitrace, textures larger than 2048 break fast clear
# optimizations on some intel drivers. We sometimes need to go larger, but
# we try to avoid it.
- name: gfx.webrender.max-shared-surface-size
type: int32_t
value: 2048
mirror: once
# Whether to use EGL robustness or not.
- name: gfx.webrender.prefer-robustness
type: bool
#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
value: true
#else
value: false
#endif
mirror: once
# Whether to use the WebRender software backend
- name: gfx.webrender.software
type: bool
value: false
mirror: once
# Whether to use the D3D11 RenderCompositor when using WebRender software backend
- name: gfx.webrender.software.d3d11
type: bool
value: true
mirror: once
- name: gfx.webrender.software.opengl
type: bool
#if defined(MOZ_WIDGET_ANDROID)
value: true
#else
value: false
#endif
mirror: once
- name: gfx.webrender.software.d3d11.upload-mode
type: RelaxedAtomicInt32
value: 4
mirror: always
# Whether to force widgets to don't support acceleration to use WebRender
# despite that
- name: gfx.webrender.unaccelerated-widget.force
type: RelaxedAtomicBool
value: false
mirror: always
# Enable a lower quality, but higher performance pinch-zoom mode. Primarily
# for devices with weak GPUs, or when running SWGL.
- name: gfx.webrender.low-quality-pinch-zoom
type: bool
#if defined(MOZ_WIDGET_ANDROID) && defined(NIGHTLY_BUILD)
value: true
#else
value: false
#endif
mirror: once
# Disable wait of GPU execution completion
- name: gfx.webrender.wait-gpu-finished.disabled
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
# Enable VideoProcessor Super Resolution for video overlay
- name: gfx.webrender.overlay-vp-super-resolution
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
# Enable VideoProcessor-HDR on SDR content for video overlay
- name: gfx.webrender.overlay-vp-auto-hdr
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
# Enable a dedicated arena on frame builder threads.
- name: gfx.webrender.frame-builder-thread-local-arena
type: bool
rust: true
value: false
mirror: once
# Enable a dedicated arena on scene builder threads.
- name: gfx.webrender.scene-builder-thread-local-arena
type: bool
rust: true
value: false
mirror: once
# Enable a dedicated arena on WebRender worker threads.
- name: gfx.webrender.worker-thread-local-arena
type: bool
rust: true
value: true
mirror: once
# Use vsync events generated by hardware
- name: gfx.work-around-driver-bugs
type: bool
value: true
mirror: once
- name: gfx.ycbcr.accurate-conversion
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.remote-texture.recycle.disabled
type: RelaxedAtomicBool
value: false
mirror: always
- name: gfx.remote-texture.wait-owner-at-image-host
type: RelaxedAtomicBool
value: false
mirror: always
#if defined(MOZ_WAYLAND)
- name: gfx.wayland.hdr
type: bool
value: false
mirror: once
#endif
#---------------------------------------------------------------------------
# Prefs starting with "gl." (OpenGL)
#---------------------------------------------------------------------------
- name: gl.allow-high-power
type: RelaxedAtomicBool
value: true
mirror: always
- name: gl.ignore-dx-interop2-blacklist
type: RelaxedAtomicBool
value: false
mirror: always
- name: gl.use-tls-is-current
type: RelaxedAtomicInt32
value: 0
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "html5."
#---------------------------------------------------------------------------
# Time in milliseconds between the time a network buffer is seen and the timer
# firing when the timer hasn't fired previously in this parse in the
# off-the-main-thread HTML5 parser.
- name: html5.flushtimer.initialdelay
type: RelaxedAtomicInt32
value: 16
mirror: always
# Time in milliseconds between the time a network buffer is seen and the timer
# firing when the timer has already fired previously in this parse.
- name: html5.flushtimer.subsequentdelay
type: RelaxedAtomicInt32
value: 16
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "idle_period."
#---------------------------------------------------------------------------
- name: idle_period.min
type: uint32_t
value: 3
mirror: always
- name: idle_period.during_page_load.min
type: uint32_t
value: 12
mirror: always
- name: idle_period.cross_process_scheduling
type: RelaxedAtomicBool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "image."
#---------------------------------------------------------------------------
# The maximum size (in kB) that the aggregate frames of an animation can use
# before it starts to discard already displayed frames and redecode them as
# necessary.
- name: image.animated.decode-on-demand.threshold-kb
type: RelaxedAtomicUint32
value: 20*1024
mirror: always
# The minimum number of frames we want to have buffered ahead of an
# animation's currently displayed frame.
- name: image.animated.decode-on-demand.batch-size
type: RelaxedAtomicUint32
value: 6
mirror: always
# Whether we should recycle already displayed frames instead of discarding
# them. This saves on the allocation itself, and may be able to reuse the
# contents as well. Only applies if generating full frames.
- name: image.animated.decode-on-demand.recycle
type: bool
value: true
mirror: once
# Resume an animated image from the last displayed frame rather than
# advancing when out of view.
- name: image.animated.resume-from-last-displayed
type: RelaxedAtomicBool
value: true
mirror: always
# Maximum number of surfaces for an image before entering "factor of 2" mode.
# This in addition to the number of "native" sizes of an image. A native size
# is a size for which we can decode a frame without up or downscaling. Most
# images only have 1, but some (i.e. ICOs) may have multiple frames for the
# same data at different sizes.
- name: image.cache.factor2.threshold-surfaces
type: RelaxedAtomicInt32
value: 4
mirror: always
# Maximum size of a surface in KB we are willing to produce when rasterizing
# an SVG.
- name: image.cache.max-rasterized-svg-threshold-kb
type: RelaxedAtomicInt32
value: 200*1024
mirror: always
# The maximum size, in bytes, of the decoded images we cache.
- name: image.cache.size
type: int32_t
value: 5*1024*1024
mirror: once
# A weight, from 0-1000, to place on time when comparing to size.
# Size is given a weight of 1000 - timeweight.
- name: image.cache.timeweight
type: int32_t
value: 500
mirror: once
# Decode all images automatically on load, ignoring our normal heuristics.
- name: image.decode-immediately.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Decode all images synchronously, intended to be used for reftests.
- name: image.testing.decode-sync.enabled
type: bool
value: false
mirror: always
# Whether we attempt to downscale images during decoding.
- name: image.downscale-during-decode.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Whether EXIF density metadata is sanity checked against PixelXDimension and PixelYDimension
- name: image.exif-density-correction.sanity-check.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# The threshold for inferring that changes to an <img> element's |src|
# attribute by JavaScript represent an animation, in milliseconds. If the |src|
# attribute is changing more frequently than this value, then we enter a
# special "animation mode" which is designed to eliminate flicker. Set to 0 to
# disable.
- name: image.infer-src-animation.threshold-ms
type: RelaxedAtomicUint32
value: 2000
mirror: always
# Whether the network request priority should be adjusted according
# the layout and view frame position of each particular image.
- name: image.layout_network_priority
type: RelaxedAtomicBool
value: true
mirror: always
# Chunk size for calls to the image decoders.
- name: image.mem.decode_bytes_at_a_time
type: uint32_t
value: 16384
mirror: once
# Discards inactive image frames and re-decodes them on demand from
# compressed data.
- name: image.mem.discardable
type: RelaxedAtomicBool
value: true
mirror: always
# Discards inactive image frames of _animated_ images and re-decodes them on
# demand from compressed data. Has no effect if image.mem.discardable is false.
- name: image.mem.animated.discardable
type: bool
value: true
mirror: once
# Enable extra information for debugging in the image memory reports.
- name: image.mem.debug-reporting
type: RelaxedAtomicBool
value: false
mirror: always
# Force unmapping of unused shared surfaces after a timeout period or when we
# encounter virtual memory pressure. By default this is only enabled on 32-bit
# Firefox.
- name: image.mem.shared.unmap.force-enabled
type: bool
value: false
mirror: once
# Minimum timeout to unmap shared surfaces since they have been last used,
# in milliseconds.
- name: image.mem.shared.unmap.min_expiration_ms
type: uint32_t
value: 60*1000
mirror: once
# Mininum size for shared surfaces to consider unmapping, in kilobytes.
- name: image.mem.shared.unmap.min_threshold_kb
type: uint32_t
value: 100
mirror: once
# How much of the data in the surface cache is discarded when we get a memory
# pressure notification, as a fraction. The discard factor is interpreted as a
# reciprocal, so a discard factor of 1 means to discard everything in the
# surface cache on memory pressure, a discard factor of 2 means to discard half
# of the data, and so forth. The default should be a good balance for desktop
# and laptop systems, where we never discard visible images.
- name: image.mem.surfacecache.discard_factor
type: uint32_t
value: 1
mirror: once
# Maximum size for the surface cache, in kilobytes.
- name: image.mem.surfacecache.max_size_kb
type: uint32_t
value: 2024 * 1024
mirror: once
# Minimum timeout for expiring unused images from the surface cache, in
# milliseconds. This controls how long we store cached temporary surfaces.
- name: image.mem.surfacecache.min_expiration_ms
type: uint32_t
value: 60*1000
mirror: once
# The surface cache's size, within the constraints of the maximum size set
# above, is determined as a fraction of main memory size. The size factor is
# interpreted as a reciprocal, so a size factor of 4 means to use no more than
# 1/4 of main memory. The default should be a good balance for most systems.
- name: image.mem.surfacecache.size_factor
type: uint32_t
value: 4
mirror: once
# Maximum size in kilobytes that we allow to allocate an imgFrame, meant for
# testing/fuzzing purposes. -1 disables this limit (there are other limits in
# place).
- name: image.mem.max_legal_imgframe_size_kb
type: RelaxedAtomicInt32
value: -1
mirror: always
# Whether we record SVG images as blobs or not.
- name: image.svg.blob-image
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to set the incremental attribute in the Priority header for images
- name: image.priority.incremental
type: RelaxedAtomicBool
value: true
mirror: always
# Whether we attempt to decode AVIF images or not.
- name: image.avif.enabled
type: RelaxedAtomicBool
#if defined(MOZ_AV1)
value: true
#else
value: false
#endif
mirror: always
# How strict we are in accepting/rejecting AVIF inputs according to whether they
# conform to the specification
# 0 = Permissive: accept whatever we can simply, unambiguously interpret
# 1 = Normal: reject violations of "shall" specification directives
# 2 = Strict: reject violations of "should" specification directives
- name: image.avif.compliance_strictness
type: RelaxedAtomicInt32
value: 1
mirror: always
# Whether we apply container-level transforms like mirroring and rotation
- name: image.avif.apply_transforms
type: RelaxedAtomicBool
value: true
mirror: always
# Whether we use dav1d (true) or libaom (false) to decode AVIF image
- name: image.avif.use-dav1d
type: RelaxedAtomicBool
value: true
mirror: always
# Whether to allow decoding of animated AVIF sequences.
- name: image.avif.sequence.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Whether AVIF files containing sequences should be animated even when the
# major brand is set to 'avif'.
- name: image.avif.sequence.animate_avif_major_branded_images
type: RelaxedAtomicBool
value: false
mirror: always
# Whether we attempt to decode JXL images or not.
- name: image.jxl.enabled
type: RelaxedAtomicBool
value: false
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "intl."
#---------------------------------------------------------------------------
#ifdef XP_WIN
# Whether Gecko creates or does not create native caret for legacy ATOK
# (2011 - 2015).
- name: intl.tsf.hack.atok.create_native_caret
type: bool
value: true
mirror: always
# Whether Gecko returns available composition string rect or TS_E_NOLAYOUT
# from ITextStoreACP::GetTextExt() when the specified range is same as the
# range of composition string but some character rects in it are still
# dirty if and only if ATOK is active TIP.
# Note that this is ignored if active ATOK is or older than 2016 and
# create_native_caret is true.
- name: intl.tsf.hack.atok.do_not_return_no_layout_error_of_composition_string
type: bool
value: true
mirror: always
# Whether Gecko sets input scope of ATOK to "search" or never does it.
# When "search" is set to the input scope, ATOK may stop their suggestions.
# To avoid it, turn this pref on, or changing the settings in ATOK.
# Note that if you enable this pref and you use the touch keyboard for touch
# screens, you cannot access some specific features for a "search" input
# field.
- name: intl.tsf.hack.atok.search_input_scope_disabled
type: bool
value: false
mirror: always
# Whether Gecko returns caret rect before composition string or TS_E_NOLAYOUT
# from ITextStoreACP::GetTextExt() when the specified range is larger than
# composition start offset if and only if Free ChangJie is active TIP.
- name: intl.tsf.hack.free_chang_jie.do_not_return_no_layout_error
type: bool
value: true
mirror: always
# Whether Gecko returns available composition string rect or TS_E_NOLAYOUT
# from ITextStoreACP::GetTextExt() when the specified range is same as the
# range of composition string but some character rects in it are still
# dirty if and only if Japanist 10 is active TIP.
- name: intl.tsf.hack.japanist10.do_not_return_no_layout_error_of_composition_string
type: bool
value: true
mirror: always
# Whether Gecko returns previous character rect or TS_E_NOLAYOUT from
# ITfContextView::GetTextExt() when the specified range is the first
# character of selected clause of composition string if and only if Japanese TIP
# of Microsoft is active.
- name: intl.tsf.hack.ms_japanese_ime.do_not_return_no_layout_error_at_first_char
type: bool
value: true
mirror: always
# Whether Gecko returns previous character rect or TS_E_NOLAYOUT from
# ITfContextView::GetTextExt() when the specified range is the caret of
# composition string if and only if Japanese TIP of Microsoft is active.
- name: intl.tsf.hack.ms_japanese_ime.do_not_return_no_layout_error_at_caret
type: bool
value: true
mirror: always
# Whether Gecko returns caret rect before composition string or TS_E_NOLAYOUT
# from ITfContextView::GetTextExt() when the specified range is larger than
# composition start offset if and only Simplified Chinese TIP of Microsoft
# is active.
- name: intl.tsf.hack.ms_simplified_chinese.do_not_return_no_layout_error
type: bool
value: true
mirror: always
# Whether Geckos hacks ITextStoreACP::QueryInsert() or not. The method should
# return new selection after specified length text is inserted at specified
# range. However, Microsoft Pinyin and Microsoft Wubi expect that the result
# is same as specified range. If following prefs are true,
# ITextStoreACP::QueryInsert() returns specified range only when one of the
# TIPs is active.
- name: intl.tsf.hack.ms_simplified_chinese.query_insert_result
type: bool
value: true
mirror: always
# Whether Gecko returns caret rect before composition string or TS_E_NOLAYOUT
# from ITfContextView::GetTextExt() when the specified range is larger than
# composition start offset if and only Traditional Chinese TIP of Microsoft
# is active.
- name: intl.tsf.hack.ms_traditional_chinese.do_not_return_no_layout_error
type: bool
value: true
mirror: always
# Whether Geckos hacks ITextStoreACP::QueryInsert() or not. The method should
# return new selection after specified length text is inserted at specified
# range. However, Microsoft ChangJie and Microsoft Quick expect that the
# result is same as specified range. If following prefs are true,
# ITextStoreACP::QueryInsert() returns specified range only when one of the
# TIPs is active.
- name: intl.tsf.hack.ms_traditional_chinese.query_insert_result
type: bool
value: true
mirror: always
# Whether Gecko sets input scope of the URL bar to IS_DEFAULT when black
# listed IMEs are active or does not. If you use tablet mode mainly and you
# want to use touch keyboard for URL when you set focus to the URL bar, you
# can set this to false. Then, you'll see, e.g., ".com" key on the keyboard.
# However, if you set this to false, such IMEs set its open state to "closed"
# when you set focus to the URL bar. I.e., input mode is automatically
# changed to English input mode.
# Known buggy IME list:
# - Microsoft IME for Japanese
# - Google Japanese Input
# - Microsoft Bopomofo
# - Microsoft ChangJie
# - Microsoft Phonetic
# - Microsoft Quick
# - Microsoft New ChangJie
# - Microsoft New Phonetic
# - Microsoft New Quick
# - Microsoft Pinyin
# - Microsoft Pinyin New Experience Input Style
# - Microsoft Wubi
# - Microsoft IME for Korean (except on Win7)
# - Microsoft Old Hangul
- name: intl.ime.hack.set_input_scope_of_url_bar_to_default
type: bool
value: true
mirror: always
# On Windows 10 Build 17643 (an Insider Preview build of RS5), Microsoft
# have fixed the caller of ITextACPStore::GetTextExt() to return
# TS_E_NOLAYOUT to TIP as-is, rather than converting to E_FAIL.
# Therefore, if TIP supports asynchronous layout computation perfectly, we
# can return TS_E_NOLAYOUT and TIP waits next OnLayoutChange()
# notification. However, some TIPs still have some bugs of asynchronous
# layout support. We keep hacking the result of GetTextExt() like running
# on Windows 10, however, there could be unknown TIP bugs if we stop
# hacking the result. So, user can stop checking build ID to make Gecko
# hack the result forcibly.
- name: intl.tsf.hack.allow_to_stop_hacking_on_build_17643_or_later
type: bool
value: @IS_EARLY_BETA_OR_EARLIER@
mirror: always
# If true, automatically extend selection to cluster boundaries when
# TSF/TIP requests to select from/by middle of a cluster.
- name: intl.tsf.hack.extend_setting_selection_range_to_cluster_boundaries
type: bool
value: @IS_NOT_EARLY_BETA_OR_EARLIER@
mirror: always
# Whether Gecko supports IMM even if TSF is enabled. This pref exists
# only for check TSF behavior of new versions. Therefore, users should
# not set this to false for daily use.
- name: intl.tsf.support_imm
type: bool
value: true
mirror: once
# If true, TSF and TIP (IME) can retrieve URL of the document containing
# the focused element. When this is set to true, Gecko exposes the spec
# of the URL.
# And Gecko exposes only "http" and "https" URLs. E.g., "data", "blob",
# "file" URLs are never exposed.
- name: intl.tsf.expose_url.allowed
type: bool
value: true
mirror: always
# If true, TSF and TIP (IME) can retrieve URL of the document containing
# the focused element in the private browsing mode too.
- name: intl.tsf.expose_url_in_private_browsing.allowed
type: bool
value: false
mirror: always
#if defined(ENABLE_TESTS)
# If true, NS_GetComplexLineBreaks compares the line breaks produced in the
# content process using the Uniscribe line breaker, with those from a
# brokered call to the parent.
- name: intl.compare_against_brokered_complex_line_breaks
type: bool
value: false
mirror: always
#endif
#endif
# If you use legacy Chinese IME which puts an ideographic space to composition
# string as placeholder, this pref might be useful. If this is true and when
# web contents forcibly commits composition (e.g., moving focus), the
# ideographic space will be ignored (i.e., commits with empty string).
- name: intl.ime.remove_placeholder_character_at_commit
type: bool
value: false
mirror: always
#if defined(XP_MACOSX) || defined(MOZ_WIDGET_GTK) || defined(ANDROID)
# Whether text input without keyboard press nor IME composition should cause a
# set of composition events or not. E.g., when you use Emoji picker on macOS,
# it inserts an Emoji character directly. If set to true, `compositionstart`,
# `compositionupdate` and `compositionend` events will be fired, and the
# correspnding `beforeinput` events are not cancelable. Otherwise, if set to
# false, any user input events are not exposed to web apps but only
# `beforeinput` event is fired as "insert text" as a cancelable event.
- name: intl.ime.use_composition_events_for_insert_text
type: bool
value: false
mirror: always
#endif
# If true, we use UAX14/29 compatible segmenter rules using ICU4X
- name: intl.icu4x.segmenter.enabled
type: RelaxedAtomicBool
value: true
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "javascript."
#
# NOTE: SpiderMonkey starts up before `mirror: once` preferences are sealed and
# prefs but mark as `do_not_use_directly` and `LoadStartupJSPrefs` will
# mirror them into SpiderMonkey.
#---------------------------------------------------------------------------
# The JavaScript JIT compilers. These are read once on startup so a browser may
# need to be restarted if toggling them. In general each subsequent JIT depends
# on the ones before it being enabled.
- name: javascript.options.blinterp
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.baselinejit
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.ion
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
# The irregexp JIT for regex evaluation.
- name: javascript.options.native_regexp
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
# Jit Hints Cache - An in-process cache for the
# content process to accelerate repeated baseline
# compilations
- name: javascript.options.jithints
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
# "Warm-up" thresholds at which we attempt to compile a script/function with
# the next JIT tier.
#
# NOTE: These must match JitOptions defaults.
- name: javascript.options.blinterp.threshold
type: int32_t
value: 10
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.baselinejit.threshold
type: int32_t
value: 100
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.ion.threshold
type: int32_t
value: 1500
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
#ifdef NIGHTLY_BUILD
# Experimental support for off-main-thread baseline compilation.
- name: javascript.options.experimental.baselinejit.offthread_compilation
type: bool
value: false
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
#endif
# Enable off-main-thread Warp compilation.
- name: javascript.options.ion.offthread_compilation
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
#ifdef DEBUG
# Enable extra correctness checks in the JITs that are slow and only available
# in debug builds.
- name: javascript.options.jit.full_debug_checks
type: bool
value: false
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
#endif
# Heuristic threshold for Warp/Ion to decide that too many bailouts are
# happening and an IonScript should be discarded.
#
# NOTE: This must match JitOptions defaults.
- name: javascript.options.ion.frequent_bailout_threshold
type: int32_t
value: 10
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
# A threshold for Warp to decide whether a function can be inlined.
# If the size of a function is smaller than this threshold, then it
# may be inlined.
#
# NOTE: These must match JitOptions defaults.
- name: javascript.options.inlining_bytecode_max_length
type: uint32_t
value: 130
mirror: always
do_not_use_directly: true
- name: javascript.options.compact_on_user_inactive
type: bool
value: true
mirror: always
# No-op pref for testing the SpiderMonkey pref system.
- name: javascript.options.tests.uint32-pref
type: uint32_t
value: 1
mirror: always
set_spidermonkey_pref: always
# The default amount of time to wait from the user being idle to starting a
# shrinking GC. Measured in milliseconds.
- name: javascript.options.compact_on_user_inactive_delay
type: uint32_t
#ifdef NIGHTLY_BUILD
value: 15000
#else
value: 300000
#endif
mirror: always
# Use the realm local dom alloc site.
- name: javascript.options.dom_alloc_site
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
# Use better error message when accessing property of null or undefined.
- name: javascript.options.property_error_message_fix
type: bool
value: @IS_NIGHTLY_OR_DEV_EDITION@
mirror: always
set_spidermonkey_pref: startup
# Whether to expose the FinalizationRegistry.prototype.cleanupSome method.
- name: javascript.options.experimental.weakrefs.expose_cleanupSome
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
- name: javascript.options.experimental.shadow_realms
# Atomic, as we assert the preference, and that assertion may happen
# in a worker.
type: RelaxedAtomicBool
value: false
mirror: always
# Non-startup pref because the WPT test harness sets prefs after startup.
set_spidermonkey_pref: always
# Experimental support for Duplicate Named Capture Groups in JavaScript.
- name: javascript.options.experimental.regexp_duplicate_named_groups
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Pattern Modifiers in JavaScript.
- name: javascript.options.experimental.regexp_modifiers
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Uint8Array base64/hex in JavaScript.
- name: javascript.options.experimental.uint8array_base64
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Promise.try in JavaScript.
- name: javascript.options.experimental.promise_try
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Math.sumPrecise in JavaScript.
- name: javascript.options.experimental.math_sumprecise
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Atomics.pause in JavaScript.
- name: javascript.options.experimental.atomics_pause
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Error.isError in JavaScript.
- name: javascript.options.experimental.error_iserror
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
#ifdef NIGHTLY_BUILD
# Experimental support for Async Iterator Helpers in JavaScript.
- name: javascript.options.experimental.async_iterator_helpers
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Symbols as WeakMap keys in JavaScript.
- name: javascript.options.experimental.symbols_as_weakmap_keys
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Iterator.range in JavaScript.
- name: javascript.options.experimental.iterator_range
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Joint Iteration in JavaScript.
- name: javascript.options.experimental.joint_iteration
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
# Experimental support for Iterator Sequencing in JavaScript.
- name: javascript.options.experimental.iterator_sequencing
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
# Experimental support for upsert in JavaScript.
- name: javascript.options.experimental.upsert
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
#endif // NIGHTLY_BUILD
# Experimental support for Temporal in JavaScript.
- name: javascript.options.experimental.temporal
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
#ifdef ENABLE_EXPLICIT_RESOURCE_MANAGEMENT
# Experimental support for Explicit Resource Management in JavaScript.
- name: javascript.options.experimental.explicit_resource_management
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
#endif // ENABLE_EXPLICIT_RESOURCE_MANAGEMENT
- name: javascript.options.experimental.error_capture_stack_trace
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.experimental.json_parse_with_source
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
# Dictionary Teleporting
- name: javascript.options.experimental.dictionary_teleporting
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.experimental.import_attributes
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_caching
type: bool
value: true
mirror: always
# The amount of time we wait between a request to GC (due to leaving a page) and doing the actual GC, in ms.
- name: javascript.options.gc_delay
type: uint32_t
value: 4000
mirror: always
# The amount of time we wait from the first request to GC to actually doing the first GC, in ms.
- name: javascript.options.gc_delay.first
type: uint32_t
value: 10000
mirror: always
# After doing a zonal GC, wait this much time (in ms) and then do a full GC,
# unless one is already pending.
- name: javascript.options.gc_delay.full
type: uint32_t
value: 60000
mirror: always
# Maximum amount of time that should elapse between incremental GC slices, in ms.
- name: javascript.options.gc_delay.interslice
type: uint32_t
value: 250
mirror: always
# nsJSEnvironmentObserver observes the memory-pressure notifications and
# forces a garbage collection and cycle collection when it happens, if the
# appropriate pref is set.
- name: javascript.options.gc_on_memory_pressure
type: bool
# Disable the JS engine's GC on memory pressure on Android for now to continue investigating its
# performance impacts and then decide to enable it or not.
value: @IS_NOT_ANDROID@
mirror: always
# We allow at most MIN(max, MAX(NUM_CPUS / cpu_divisor, 1)) concurrent GCs
# between processes
- name: javascript.options.concurrent_multiprocess_gcs.cpu_divisor
type: RelaxedAtomicUint32
value: 4
mirror: always
# See 'cpu_divisor' above, 0 means UINT_32_MAX.
- name: javascript.options.concurrent_multiprocess_gcs.max
type: RelaxedAtomicUint32
value: 0
mirror: always
- name: javascript.options.mem.log
type: bool
value: false
mirror: always
- name: javascript.options.mem.notify
type: bool
value: false
mirror: always
# Whether the Parent process allocates and shares memory with all content
# processes. This is mirrored once, as the parent process will do this
# allocation early on.
- name: javascript.options.self_hosted.use_shared_memory
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.main_thread_stack_quota_cap
type: uint32_t
#if defined(MOZ_ASAN)
value: 6 * 1024 * 1024
#else
value: 2 * 1024 * 1024
#endif
mirror: always
- name: javascript.options.wasm_disable_huge_memory
type: bool
value: false
mirror: always
set_spidermonkey_pref: startup
- name: javascript.options.wasm_optimizingjit
type: bool
value: true
mirror: always
- name: javascript.options.wasm_relaxed_simd
type: bool
#if defined(ENABLE_WASM_RELAXED_SIMD)
value: @IS_NIGHTLY_BUILD@
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_moz_intgemm
type: bool
#if defined(ENABLE_WASM_MOZ_INTGEMM)
value: @IS_NIGHTLY_BUILD@
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: startup
- name: javascript.options.wasm_exnref
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
- name: javascript.options.wasm_gc
type: bool
#if defined(ENABLE_WASM_GC)
value: true
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_memory_control
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_branch_hinting
type: bool
#if defined(ENABLE_WASM_BRANCH_HINTING)
value: @IS_NIGHTLY_BUILD@
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
#if defined(ENABLE_WASM_SIMD)
#if defined(JS_CODEGEN_X64) || defined(JS_CODEGEN_X86)
# Enables AVX instructions support on X86/X64 platforms.
# Changing these prefs requires a restart.
- name: javascript.options.wasm_simd_avx
type: bool
value: true
mirror: always
set_spidermonkey_pref: startup
#endif
#endif
- name: javascript.options.wasm_memory64
type: bool
#if defined(ENABLE_WASM_MEMORY64)
value: true
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_multi_memory
type: bool
#if defined(ENABLE_WASM_MULTI_MEMORY)
value: true
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_js_string_builtins
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_tail_calls
type: bool
#if defined(ENABLE_WASM_TAIL_CALLS)
value: true
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_js_promise_integration
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
- name: javascript.options.wasm_test_serialization
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
# Enables lazy tiering for wasm modules that have a GC type defined in them.
# Use wasm_lazy_tiering to enable it for any module.
- name: javascript.options.wasm_lazy_tiering_for_gc
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
# Enables lazy tiering for all modules. Use wasm_lazy_tiering_for_gc to only
# enable this for GC modules.
- name: javascript.options.wasm_lazy_tiering
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
# Aggressiveness of lazy tiering, allowable: 1 .. 9
# 1 = min (almost never, set tiering threshold to max possible, == 2^31-1)
# 9 = max (request tier up at first call, set tiering threshold to zero)
- name: javascript.options.wasm_lazy_tiering_level
type: uint32_t
value: 5
mirror: always
set_spidermonkey_pref: always
# Forces lazy tiering to synchronously compile instead of using a background
# thread.
- name: javascript.options.wasm_lazy_tiering_synchronous
type: bool
value: false
mirror: always
set_spidermonkey_pref: always
# Aggressiveness of inlining (regardless of call kind), allowable: 1 .. 9
- name: javascript.options.wasm_inlining_level
type: uint32_t
value: 5
mirror: always
set_spidermonkey_pref: always
# Are wasm direct calls (within same Instance) candidates for inlining?
- name: javascript.options.wasm_direct_inlining
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
# Are wasm call_ref calls (within same Instance) candidates for inlining?
- name: javascript.options.wasm_call_ref_inlining
type: bool
value: true
mirror: always
set_spidermonkey_pref: always
# When selecting call_ref targets for speculative inlining, this is the minimum
# percentage of the total number of calls from the call site that a candidate
# set of targets must collectively have in order to be elegible for inlining.
# Allowable: 10 .. 100 (%). Setting it (eg) 75 means the targets must collectively
# be 75% of all observed calls to be considered for inlining. Probably unwise to
# let this be much below 40.
- name: javascript.options.wasm_call_ref_inlining_percent
type: uint32_t
value: 40
mirror: always
set_spidermonkey_pref: always
# Support for pretenuring allocations based on their allocation site.
- name: javascript.options.site_based_pretenuring
type: bool
value: true
mirror: always
do_not_use_directly: true
set_spidermonkey_pref: startup
#if defined(DEBUG) || defined(NIGHTLY_BUILD) || defined(JS_GC_ZEAL)
# Enable extra poisoning of GC memory.
- name: javascript.options.extra_gc_poisoning
type: bool
#ifdef DEBUG
value: true
#else
value: false
#endif
mirror: always
set_spidermonkey_pref: startup
#endif
#if !defined(JS_CODEGEN_MIPS64) && !defined(JS_CODEGEN_LOONG64)
# Spectre security vulnerability mitigations for the JS JITs.
#
# NOTE: The MIPS and LoongArch backends do not support these mitigations (and generally
# do not need them). In that case, leave the pref unlisted with its
# default value of false.
- name: javascript.options.spectre.index_masking
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.spectre.object_mitigations
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.spectre.string_mitigations
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.spectre.value_masking
type: bool
value: true
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
- name: javascript.options.spectre.jit_to_cxx_calls
type: bool
value: false
mirror: always # LoadStartupJSPrefs
do_not_use_directly: true
#endif // !defined(JS_CODEGEN_MIPSXX) && !defined(JS_CODEGEN_LOONG64)
# Separate pref to override the values of the Spectre-related prefs above for
# isolated web content processes, where we don't need these mitigations.
- name: javascript.options.spectre.disable_for_isolated_content
type: bool
value: true
mirror: always
# Whether the W^X policy is enforced to mark JIT code pages as either writable
# or executable but never both at the same time. OpenBSD defaults to W^X.
- name: javascript.options.content_process_write_protect_code
type: bool
#if defined(XP_OPENBSD)
value: true
#else
value: false
#endif
mirror: always
# Whether to use the XPCOM thread pool for JS helper tasks.
- name: javascript.options.external_thread_pool
type: bool
value: true
mirror: always
do_not_use_directly: true
# Whether to use the off-thread script compilation and decoding.
- name: javascript.options.parallel_parsing
type: bool
value: true
mirror: always
# Whether to use fdlibm for Math.sin, Math.cos, and Math.tan. When
# privacy.resistFingerprinting is true, this pref is ignored and fdlibm is used
# anyway.
- name: javascript.options.use_fdlibm_for_sin_cos_tan
type: bool
#if defined(XP_WIN)
value: false
#else
value: true
#endif
mirror: always
set_spidermonkey_pref: always
# Whether to support parsing '//(#@) source(Mapping)?URL=' pragmas.
- name: javascript.options.source_pragmas
type: bool
value: true
mirror: always
# asm.js
- name: javascript.options.asmjs
type: bool
value: true
mirror: always
# Whether to throw a TypeError if asm.js code hits validation failure.
- name: javascript.options.throw_on_asmjs_validation_failure
type: bool
value: false
mirror: always
# Whether to disable the jit within the main process
- name: javascript.options.main_process_disable_jit
type: bool
#ifdef XP_IOS
value: true
#else
value: false
#endif
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "layers."
#---------------------------------------------------------------------------
# Whether to disable acceleration for all widgets.
- name: layers.acceleration.disabled
type: bool
value: false
mirror: once
do_not_use_directly: true
# Instead, use gfxConfig::IsEnabled(Feature::HW_COMPOSITING).
# Whether to force acceleration on, ignoring blacklists.
- name: layers.acceleration.force-enabled
type: bool
value: false
mirror: once
do_not_use_directly: true
# Whether we allow AMD switchable graphics.
- name: layers.amd-switchable-gfx.enabled
type: bool
value: true
mirror: once
# Whether to use async panning and zooming.
- name: layers.async-pan-zoom.enabled
type: bool
value: true
mirror: once
do_not_use_directly: true
- name: layers.d3d11.force-warp
type: bool
value: false
mirror: once
- name: layers.d3d11.enable-blacklist
type: bool
value: true
mirror: once
# Enable DEAA antialiasing for transformed layers in the compositor.
- name: layers.deaa.enabled
type: RelaxedAtomicBool
#if defined(MOZ_WIDGET_ANDROID)
value: false
#else
value: true
#endif
mirror: always
# Force all possible layers to be always active layers.
- name: layers.force-active
type: bool
value: false
mirror: always
- name: layers.draw-mask-debug
type: RelaxedAtomicBool
value: false
mirror: always
- name: layers.force-synchronous-resize
type: RelaxedAtomicBool
#ifdef MOZ_WAYLAND
# We want to control it by nsWindow::SynchronouslyRepaintOnResize() on Linux/Wayland.
value: false
#else
value: true
#endif
mirror: always
- name: layers.gpu-process.allow-software
type: bool
#if defined(XP_WIN)
value: true
#else
value: false
#endif
mirror: once
- name: layers.gpu-process.enabled
type: bool
#if defined(XP_WIN) || defined(MOZ_WIDGET_ANDROID)
value: true
#elif defined(MOZ_X11)
#else
value: false
#endif
mirror: once
- name: layers.gpu-process.force-enabled
type: bool
value: false
mirror: once
- name: layers.gpu-process.ipc_reply_timeout_ms
type: int32_t
value: 10000
mirror: once
- name: layers.gpu-process.extend_ipc_reply_timeout_ms
type: int32_t
value: 20000
mirror: once
# How many unstable GPU process restarts we allow for a given configuration.
- name: layers.gpu-process.max_restarts
type: RelaxedAtomicInt32
#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK) || defined(MOZ_WIDGET_ANDROID)
value: 6
#else
value: 1
#endif
mirror: always
# How many frames we must render before declaring the GPU process stable, and
# allow restarts without it counting against our maximum restarts.
- name: layers.gpu-process.stable.frame-threshold
type: RelaxedAtomicUint32
value: 10
mirror: always
# How many milliseconds the GPU process must have lived before we accept that
# it is stable, and allow restarts without it counting against our maximum
# restarts.
- name: layers.gpu-process.stable.min-uptime-ms
type: RelaxedAtomicInt32
value: 4 * 60000
mirror: always
# Note: This pref will only be used if it is less than layers.gpu-process.max_restarts.
- name: layers.gpu-process.max_restarts_with_decoder
type: RelaxedAtomicInt32
value: 0
mirror: always
- name: layers.gpu-process.startup_timeout_ms
type: int32_t
value: 5000
mirror: once
- name: layers.gpu-process.crash-also-crashes-browser
type: bool
value: false
mirror: always
# Whether to animate simple opacity and transforms on the compositor.
- name: layers.offmainthreadcomposition.async-animations
type: bool
value: true
mirror: always
# Whether to log information about off main thread animations to stderr.
- name: layers.offmainthreadcomposition.log-animations
type: bool
value: false
mirror: always
- name: layers.offmainthreadcomposition.force-disabled
type: bool
value: false
mirror: once
# Compositor target frame rate. NOTE: If vsync is enabled the compositor
# frame rate will still be capped.
# -1 -> default (match layout.frame_rate or 60 FPS)
# 0 -> full-tilt mode: Recomposite even if not transaction occured.
- name: layers.offmainthreadcomposition.frame-rate
type: RelaxedAtomicInt32
value: -1
mirror: always
#ifdef XP_WIN
- name: layers.prefer-opengl
type: bool
value: false
mirror: once
#endif
# Copy-on-write canvas.
- name: layers.shared-buffer-provider.enabled
type: RelaxedAtomicBool
value: true
mirror: always
- name: layers.recycle-allocator-rdd
type: bool
value: true
mirror: once
- name: layers.iosurfaceimage.recycle-limit
type: RelaxedAtomicUint32
value: 15
mirror: always
#---------------------------------------------------------------------------
# Prefs starting with "layout."
#---------------------------------------------------------------------------
# Debug-only pref to force enable the AccessibleCaret. If you want to
# control AccessibleCaret by mouse, you'll need to set
# "layout.accessiblecaret.hide_carets_for_mouse_input" to false.
- name: layout.accessiblecaret.enabled
type: bool
value: false
mirror: always
# Enable the accessible caret on platforms/devices
# that we detect have touch support. Note that this pref is an
# additional way to enable the accessible carets, rather than
# overriding the layout.accessiblecaret.enabled pref.
- name: layout.accessiblecaret.enabled_on_touch
type: bool
value: true
mirror: always
# By default, carets become tilt only when they are overlapping.
- name: layout.accessiblecaret.always_tilt
type: bool
value: false
mirror: always
# Show caret in cursor mode when long tapping on an empty content. This
# also changes the default update behavior in cursor mode, which is based
# on the emptiness of the content, into something more heuristic. See
# AccessibleCaretManager::UpdateCaretsForCursorMode() for the details.
- name: layout.accessiblecaret.caret_shown_when_long_tapping_on_empty_content
type: bool
value: false
mirror: always
# 0 = by default, always hide carets for selection changes due to JS calls.
# 1 = update any visible carets for selection changes due to JS calls,
# but don't show carets if carets are hidden.
# 2 = always show carets for selection changes due to JS calls.
- name: layout.accessiblecaret.script_change_update_mode
type: int32_t
value: 0
mirror: always
# Allow one caret to be dragged across the other caret without any limitation.
# This matches the built-in convention for all desktop platforms.
- name: layout.accessiblecaret.allow_dragging_across_other_caret
type: bool
value: true
mirror: always
# Optionally provide haptic feedback on long-press selection events.
- name: layout.accessiblecaret.hapticfeedback
type: bool
value: false
mirror: always
# Smart phone-number selection on long-press is not enabled by default.
- name: layout.accessiblecaret.extend_selection_for_phone_number
type: bool
value: false
mirror: always
# Keep the accessible carets hidden when the user is using mouse input (as
# opposed to touch/pen/etc.).
- name: layout.accessiblecaret.hide_carets_for_mouse_input
type: bool
value: true
mirror: always
# CSS attributes (width, height, margin-left) of the AccessibleCaret in CSS
# pixels.
- name: layout.accessiblecaret.width
type: float
value: 34.0f
mirror: always
- name: layout.accessiblecaret.height
type: float
value: 36.0f
mirror: always
- name: layout.accessiblecaret.margin-left
type: float
value: -18.5f
mirror: always
- name: layout.accessiblecaret.transition-duration
type: float
value: 250.0f
mirror: always
# Simulate long tap events to select words. Mainly used in manual testing
# with mouse.
- name: layout.accessiblecaret.use_long_tap_injector
type: bool
value: false
mirror: always
# To support magnify glass, whether we dispatch additional chrome event such as
# dragcaret.
- name: layout.accessiblecaret.magnifier.enabled
type: bool
value: @IS_ANDROID@
mirror: always
# One of several prefs affecting the maximum area to pre-render when animating
# a large element on the compositor.
# This pref enables transform (and transform like properties) animations on a
# large element run on the compositor with rendering partial area of the
# element on the main thread instead of rendering the whole area. Once the
# animation tried to composite out of the partial rendered area, the animation
# is rendered again with the latest visible partial area.
- name: layout.animation.prerender.partial
type: RelaxedAtomicBool
value: false
mirror: always
# One of several prefs affecting the maximum area to pre-render when animating
# a large element on the compositor.
# This value is applied to both x and y axes and a perfect square contructed
# by the greater axis value which will be capped by the absolute limits is used
# for the partial pre-render area.
- name: layout.animation.prerender.viewport-ratio-limit
type: AtomicFloat
value: 1.125f
mirror: always
# One of several prefs affecting the maximum area to pre-render when animating
# a large element on the compositor.
- name: layout.animation.prerender.absolute-limit-x
type: RelaxedAtomicUint32
value: 4096
mirror: always
# One of several prefs affecting the maximum area to pre-render when animating
# a large element on the compositor.
- name: layout.animation.prerender.absolute-limit-y
type: RelaxedAtomicUint32
value: 4096
mirror: always
# Test-only pref, if this is true, partial pre-rendered transform animations
# get stuck when it reaches to the pre-rendered boundaries and the pre-render
# region is never updated.
- name: layout.animation.prerender.partial.jank
type: RelaxedAtomicBool
value: false
mirror: always
# Whether to enable CSS Anchor Positioning support.
- name: layout.css.anchor-positioning.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Override DPI. A value of -1 means use the maximum of 96 and the system DPI.
# A value of 0 means use the system DPI. A positive value is used as the DPI.
# This sets the physical size of a device pixel and thus controls the
# interpretation of physical units such as "pt".
- name: layout.css.dpi
type: int32_t
value: -1
mirror: always
# Whether to always underline links.
- name: layout.css.always_underline_links
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether to respect align-content on blocks.
- name: layout.css.align-content.blocks.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether content-box and stroke-box are enabled for transform-box.
- name: layout.css.transform-box-content-stroke.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether transition-behavior property is enabled?
- name: layout.css.transition-behavior.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether @starting-style is enabled?
- name: layout.css.starting-style-at-rules.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether style() container queries are enabled
- name: layout.css.style-queries.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Should we look for counter ancestor scopes first?
- name: layout.css.counter-ancestor-scope.enabled
type: bool
value: true
mirror: always
# Whether the `-moz-control-character-visibility` property is exposed to
# content.
#
# Only for testing purposes.
- name: layout.css.moz-control-character-visibility.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether the `-moz-user-input` property is exposed to content.
- name: layout.css.moz-user-input.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# This pref controls whether the `prefers-color-scheme` value of iframes images
# reacts to the embedder `color-scheme` in content.
- name: layout.css.iframe-embedder-prefers-color-scheme.content.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Controls the transparency of the initial about:blank document. Generally you
# don't ever want a white flash in dark mode, but due to backwards compat we
# have some extra control over this, for now at least.
#
#
# Values:
# 1: content-inaccessible top-level only.
# 2: frames and content-inaccessible top-level only.
# 3: always
# Others: don't treat this document specially.
- name: layout.css.initial-document-transparency
type: RelaxedAtomicInt32
value: 3
mirror: always
# The minimum contrast ratio between the accent color background and white.
#
# We don't use this for text, so we need a contrast of at least AA (for user
# interface components and graphical objects), which per WCAG is 3:1.
#
# However that causes some colors that are realistically fine to get darkened,
# so we lower it a little bit. Eventually we should maybe use something like
# APCA or so perhaps, see:
#
#
# See also:
#
#
# For testing this.
- name: layout.css.accent-color.min-contrast-ratio
type: AtomicFloat
value: 2.4
mirror: always
# The target contrast ratio between the accent color foreground and background
# colors when darkening.
#
# We aim a bit further than the minimum contrast ratio, which seems to provide
# nice results in practice.
- name: layout.css.accent-color.darkening-target-contrast-ratio
type: AtomicFloat
value: 6.0
mirror: always
# Whether the `animation-composition` in css-animations-2 is enabled.
- name: layout.css.animation-composition.enabled
type: bool
value: true
mirror: always
# Is the codepath for using cached scrollbar styles enabled?
- name: layout.css.cached-scrollbar-styles.enabled
type: bool
value: true
mirror: always
# Are implicit tracks in computed grid templates serialized?
- name: layout.css.serialize-grid-implicit-tracks
type: RelaxedAtomicBool
value: true
mirror: always
# Whether the system-ui generic family is enabled.
- name: layout.css.system-ui.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Set the number of device pixels per CSS pixel. A value <= 0 means choose
# automatically based on user settings for the platform (e.g., "UI scale factor"
# on Mac). If browser.display.os-zoom-behavior == 1, then a positive value
# will be multiplied by the text scale factor; otherwise a positive value is
# used as-is. This controls the size of a CSS "px" at 100% full-zoom.
# The size of system fonts is also changed in proportion with the change in
# "px" sizes. Use "ui.textScaleFactor" instead to only change the size of "px".
# This is only used for windows on the screen, not for printing.
- name: layout.css.devPixelsPerPx
type: AtomicFloat
value: -1.0f
mirror: always
# Is support for CSS backdrop-filter enabled?
- name: layout.css.backdrop-filter.enabled
type: bool
value: true
mirror: always
# Do we override the blocklist for CSS backdrop-filter?
- name: layout.css.backdrop-filter.force-enabled
type: bool
value: false
mirror: always
# Is support for rect() enabled?
- name: layout.css.basic-shape-rect.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for shape() enabled?
- name: layout.css.basic-shape-shape.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
rust: true
# Is support for xywh() enabled?
- name: layout.css.basic-shape-xywh.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether alt text in content is enabled.
- name: layout.css.content.alt-text.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Should stray control characters be rendered visibly?
- name: layout.css.control-characters.visible
type: RelaxedAtomicBool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
rust: true
# Whether the `contain-intrinsic-size` CSS property is enabled
- name: layout.css.contain-intrinsic-size.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for GeometryUtils.convert*FromNode enabled?
- name: layout.css.convertFromNode.enabled
type: bool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
- name: layout.css.cross-fade.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Is support for light-dark() on content enabled?
- name: layout.css.light-dark.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for fit-content() enabled?
- name: layout.css.fit-content-function.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether to use tight bounds for floating ::first-letter (legacy Gecko behavior)
# or loose bounds based on overall font metrics (WebKit/Blink-like behavior)?
# Values mean:
# 1 legacy Gecko behavior (tight bounds)
# 0 loose typographic bounds (similar to webkit/blink)
# -1 auto behavior: use loose bounds if reduced line-height (<1em) or negative
# block-start margin is present; otherwise use tight bounds.
- name: layout.css.floating-first-letter.tight-glyph-bounds
type: int32_t
#ifdef NIGHTLY_BUILD
value: -1
#else
value: 1
#endif
mirror: always
# Is support for the @font-palette-values rule and font-palette property enabled?
- name: layout.css.font-palette.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for variation fonts enabled?
- name: layout.css.font-variations.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for the size-adjust @font-face descriptor enabled?
- name: layout.css.size-adjust.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for the tech() function in the @font-face src descriptor enabled?
- name: layout.css.font-tech.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for font-variant-emoji enabled?
- name: layout.css.font-variant-emoji.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
rust: true
# Visibility level of font families available to CSS font-matching:
# 1 - only base system fonts
# 2 - also fonts from optional language packs
# 3 - also user-installed fonts
- name: layout.css.font-visibility
type: int32_t
value: 3
mirror: always
# Is support for GeometryUtils.getBoxQuads enabled?
- name: layout.css.getBoxQuads.enabled
type: bool
value: @IS_NOT_RELEASE_OR_BETA@
mirror: always
# Is support for (linear|radial|conic)-gradient color interpolation methods enabled?
- name: layout.css.gradient-color-interpolation-method.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Should we propagate baseline alignment information from a parent grid into
# its subgrids?
- name: layout.css.grid-subgrid-baselines.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
# Is support for CSS masonry layout enabled?
- name: layout.css.grid-template-masonry-value.enabled
type: RelaxedAtomicBool
#if defined(NIGHTLY_BUILD) || defined(MOZ_THUNDERBIRD)
value: true
#else
value: false
#endif
mirror: always
rust: true
# Perform intrinsic sizing of flexible grid tracks based on grid items that
# span more than one track.
- name: layout.css.grid-flex-spanning-items-intrinsic-sizing.enabled
type: bool
value: true
mirror: always
# Enable the new multi-pass grid track sizing algorithm.
# This features implements two aspects from the CSS Grid Level 2 spec:
# 1. Percent-valued row track size re-resolution:
# 2. Multi-pass grid sizing algorithm:
- name: layout.css.grid-multi-pass-track-sizing.enabled
type: bool
value: false
mirror: always
# Is support for :has() enabled?
- name: layout.css.has-selector.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether the `:has-slotted` pseudo class is enabled
- name: layout.css.has-slotted-selector.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is support for CSS hyphenate-limit-chars enabled?
- name: layout.css.hyphenate-limit-chars.enabled
type: RelaxedAtomicBool
value: true
mirror: always
# Is support for CSS initial-letter property enabled?
- name: layout.css.initial-letter.enabled
type: bool
value: false
mirror: always
# Is eager first-letter processing during intrinsic size computation enabled?
- name: layout.css.intrinsic-size-first-letter.enabled
type: bool
value: true
mirror: always
# Which model to use for CSS letter-spacing:
# 0 - Gecko legacy model, spacing added to trailing side of letter
# 1 - WebKit/Blink-compatible, spacing always added to right-hand side
# 2 - Symmetrical spacing, half added to each side
- name: layout.css.letter-spacing.model
type: int32_t
#if defined(MOZ_DEV_EDITION) || defined(EARLY_BETA_OR_EARLIER)
value: 2
#else
value: 0
#endif
mirror: always
# Is support for motion-path url enabled?
- name: layout.css.motion-path-url.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Pref to control whether the ::marker property restrictions defined in [1]
# apply.
#
- name: layout.css.marker.restricted
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is -moz-osx-font-smoothing enabled? (Only supported in OSX builds)
- name: layout.css.osx-font-smoothing.enabled
type: bool
#if defined(XP_MACOSX)
value: true
#else
value: false
#endif
mirror: always
# Is support for CSS overflow-clip-box enabled for non-UA sheets?
- name: layout.css.overflow-clip-box.enabled
type: bool
value: false
mirror: always
# Is support for CSS overflow: -moz-hidden-unscrollable enabled
- name: layout.css.overflow-moz-hidden-unscrollable.enabled
type: RelaxedAtomicBool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
rust: true
# Is support for overscroll-behavior enabled?
- name: layout.css.overscroll-behavior.enabled
type: bool
value: true
mirror: always
# Enables support for the page-orientation property inside of CSS @page rules.
- name: layout.css.page-orientation.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Enables support for different CSS page sizes on each page when printing.
- name: layout.css.allow-mixed-page-sizes
type: RelaxedAtomicBool
value: true
mirror: always
# Enables support for @margin rules.
- name: layout.css.margin-rules.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether Properties and Values is enabled
- name: layout.css.properties-and-values.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether @scope rule is enabled
- name: layout.css.at-scope.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
rust: true
# An override for prefers-color-scheme for content documents.
# 0: Dark
# 1: Light
# 2: Auto (system color scheme unless overridden by browser theme)
- name: layout.css.prefers-color-scheme.content-override
type: RelaxedAtomicInt32
value: 2
mirror: always
# Dictates whether or not the prefers-reduced-transparency media query is enabled.
- name: layout.css.prefers-reduced-transparency.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Dictates whether or not the inverted-colors media query is enabled.
- name: layout.css.inverted-colors.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Is support for -moz-prefixed animation properties enabled?
- name: layout.css.prefixes.animations
type: bool
value: true
mirror: always
# Is support for -moz-border-image enabled?
- name: layout.css.prefixes.border-image
type: bool
value: true
mirror: always
# Is support for -moz-box-sizing enabled?
- name: layout.css.prefixes.box-sizing
type: bool
value: true
mirror: always
# Is support for -moz-prefixed font feature properties enabled?
- name: layout.css.prefixes.font-features
type: bool
value: true
mirror: always
# Is support for -moz-prefixed transform properties enabled?
- name: layout.css.prefixes.transforms
type: bool
value: true
mirror: always
# Is support for -moz-prefixed transition properties enabled?
- name: layout.css.prefixes.transitions
type: bool
value: true
mirror: always
- name: layout.css.relative-color-syntax.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Is CSS error reporting enabled?
- name: layout.css.report_errors
type: bool
value: true
mirror: always
# Are inter-character ruby annotations enabled?
- name: layout.css.ruby.intercharacter.enabled
type: bool
value: false
mirror: always
- name: layout.css.scroll-behavior.damping-ratio
type: AtomicFloat
value: 1.0f
mirror: always
# Tuning of the smooth scroll motion used by CSSOM-View scroll-behavior.
# Spring-constant controls the strength of the simulated MSD
# (Mass-Spring-Damper).
- name: layout.css.scroll-behavior.spring-constant
type: AtomicFloat
value: 250.0f
mirror: always
# Whether the scroll-driven animations generated by CSS is enabled. This
# also include animation-timeline property.
- name: layout.css.scroll-driven-animations.enabled
type: RelaxedAtomicBool
value: @IS_NIGHTLY_BUILD@
mirror: always
rust: true
# When selecting the snap point for CSS scroll snapping, the velocity of the
# scroll frame is clamped to this speed, in CSS pixels / s.
- name: layout.css.scroll-snap.prediction-max-velocity
type: RelaxedAtomicInt32
value: 2000
mirror: always
# When selecting the snap point for CSS scroll snapping, the velocity of the
# scroll frame is integrated over this duration, in seconds. The snap point
# best suited for this position is selected, enabling the user to perform fling
# gestures.
- name: layout.css.scroll-snap.prediction-sensitivity
type: AtomicFloat
value: 0.750f
mirror: always
# Stylo thread-pool size.
# Negative means auto, 0 disables the thread-pool (main-thread styling), other
# numbers override as specified.
# Note that 1 still creates a thread-pool of one thread!
- name: layout.css.stylo-threads
type: RelaxedAtomicInt32
value: -1
mirror: always
rust: true
# Stylo work unit size. This is the amount of nodes we'll process in a single
# unit of work of the thread-pool.
#
# Larger values will increase style sharing cache hits and general DOM locality
# at the expense of decreased opportunities for parallelism. There are some
# slightly different values for the work unit size.
#
# If the size is significantly increased, make sure to also review
# stylo-local-work-queue prefs, since we might end up doing too much work
# sequentially.
#
# A value of 0 disables parallelism altogether.
- name: layout.css.stylo-work-unit-size
type: RelaxedAtomicUint32
value: 16
mirror: always
rust: true
# The minimum amount of work that a thread doing styling will try to keep
# locally before sending work to other threads, in a worker.
- name: layout.css.stylo-local-work-queue.in-worker
type: RelaxedAtomicUint32
value: 0
mirror: always
rust: true
# As above but for the main thread. The main thread can't really steal from
# other threads so it might want a bigger min queue size before giving work to
# other threads.
- name: layout.css.stylo-local-work-queue.in-main-thread
type: RelaxedAtomicUint32
value: 32
mirror: always
rust: true
# Are counters for implemented CSS properties enabled?
- name: layout.css.use-counters.enabled
type: bool
value: true
mirror: always
# Are counters for unimplemented CSS properties enabled?
- name: layout.css.use-counters-unimplemented.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Should the :visited selector ever match (otherwise :link matches instead)?
- name: layout.css.visited_links_enabled
type: bool
value: true
mirror: always
# The margin used for detecting relevancy for `content-visibility: auto`.
- name: layout.css.content-visibility-relevant-content-margin
type: float
value: 50 # 50%
mirror: always
# Whether the `hanging` and `each-line` keywords are supported by `text-indent`
- name: layout.css.text-indent-keywords.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether the "modern" uppercase mapping of ß to ẞ (rather than SS) is used.
- name: layout.css.text-transform.uppercase-eszett.enabled
type: bool
value: false
mirror: always
- name: layout.css.text-wrap-balance.enabled
type: bool
value: true
mirror: always
# Maximum number of lines to try balancing.
- name: layout.css.text-wrap-balance.limit
type: int32_t
value: 10
mirror: always
- name: layout.css.text-wrap-balance-after-clamp.enabled
type: bool
value: true
mirror: always
- name: layout.css.text-align.justify-only-after-last-tab
type: bool
value: true
mirror: always
# Support for the css Zoom property.
- name: layout.css.zoom.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
- name: layout.css.h1-in-section-ua-styles.enabled
type: RelaxedAtomicBool
value: @IS_NOT_NIGHTLY_BUILD@
mirror: always
# The maximum width or height of the cursor we should allow when intersecting
# the UI, in CSS pixels.
- name: layout.cursor.block.max-size
type: uint32_t
value: 32
mirror: always
- name: layout.cursor.disable-for-popups
type: bool
value: true
mirror: always
- name: layout.display-list.build-twice
type: RelaxedAtomicBool
value: false
mirror: always
# Toggle retaining display lists between paints.
- name: layout.display-list.retain
type: RelaxedAtomicBool
value: true
mirror: always
# Toggle retaining display lists between paints.
- name: layout.display-list.retain.chrome
type: RelaxedAtomicBool
value: true
mirror: always
- name: layout.display-list.retain.sc
type: RelaxedAtomicBool
value: false
mirror: always
# Set the maximum number of modified frames allowed before doing a full
# display list rebuild.
- name: layout.display-list.rebuild-frame-limit
type: RelaxedAtomicUint32
value: 500
mirror: always
# Pref to dump the display list to the log. Useful for debugging drawing.
- name: layout.display-list.dump
type: RelaxedAtomicBool
value: false
mirror: always
# Pref to dump the display list to the log. Useful for debugging drawing.
- name: layout.display-list.dump-content
type: RelaxedAtomicBool
value: false
mirror: always
# Pref to dump the display list to the log. Useful for debugging drawing.
- name: layout.display-list.dump-parent
type: RelaxedAtomicBool
value: false
mirror: always
- name: layout.display-list.show-rebuild-area
type: RelaxedAtomicBool
value: false
mirror: always
- name: layout.display-list.improve-fragmentation
type: RelaxedAtomicBool
value: true
mirror: always
# Are dynamic reflow roots enabled?
- name: layout.dynamic-reflow-roots.enabled
type: bool
value: @IS_EARLY_BETA_OR_EARLIER@
mirror: always
# Enables the mechanism to optimize away flex item's final reflow.
# Warning: Disabling the pref will impact the performance. This is useful only for
# debugging flexbox issues.
- name: layout.flexbox.item-final-reflow-optimization.enabled
type: bool
value: true
mirror: always
# Enables the <input type=search> custom layout frame with a clear icon.
- name: layout.forms.input-type-search.enabled
type: bool
value: false
mirror: always
# Enables the Reveal Password button inside a <input type=password>.
- name: layout.forms.reveal-password-button.enabled
type: bool
value: false
mirror: always
# If enabled, textareas won't include 'overflow:auto' scrollbars in their
# block-axis size (usually height).
- name: layout.forms.textarea-sizing-excludes-auto-scrollbar.enabled
type: bool
value: true
mirror: always
# Pref to control browser frame rate, in Hz. A value <= 0 means choose
# automatically based on knowledge of the platform (or 60Hz if no platform-
# specific information is available).
- name: layout.frame_rate
type: RelaxedAtomicInt32
value: -1
mirror: always
# If it has been this many frame periods since a refresh, assume that painting
# is quiescent (will not happen again soon).
- name: layout.idle_period.required_quiescent_frames
type: uint32_t
value: 2
mirror: always
# The amount of time (milliseconds) needed between an idle period's
# end and the start of the next tick to avoid jank.
- name: layout.idle_period.time_limit
type: uint32_t
value: 1
mirror: always
# The minimum amount of time (milliseconds) required to be remaining
# in the current vsync interval for us to attempt an extra tick, or
# <0 to disable extra ticks entirely.
- name: layout.extra-tick.minimum-ms
type: int32_t
value: 4
mirror: always
# Whether to load the broken image icon eagerly. This is mostly needed for
# reftests, since the broken image icon doesn't block the load event and thus
# there's no easy way to guarantee it's loaded.
- name: layout.image.eager_broken_image_icon
type: bool
value: false
mirror: always
# Enable/disable interruptible reflow, which allows reflows to stop
# before completion (and display the partial results) when user events
# are pending.
- name: layout.interruptible-reflow.enabled
type: bool
value: true
mirror: always
# On Android, don't synth mouse move events after scrolling, as they cause
# satisfactorily resolved.
- name: layout.reflow.synthMouseMove
type: bool
value: @IS_NOT_MOBILE@
mirror: always
# This pref determines which side vertical scrollbars should be on.
# 0 = end-side in UI direction
# 1 = end-side in document/content direction
# 2 = right
# 3 = left
- name: layout.scrollbar.side
type: int32_t
value: 0
mirror: always
# This pref is to be set by test code only.
- name: layout.scrollbars.always-layerize-track
type: RelaxedAtomicBool
value: false
mirror: always
- name: layout.scrollbars.click_and_hold_track.continue_to_end
type: bool
# On Linux, click-and-hold on the scrollbar track should continue scrolling
# until the mouse is released. On the other platforms we want to stop
# scrolling as soon as the scrollbar thumb has reached the current mouse
# position.
#ifdef MOZ_WIDGET_GTK
value: true
#else
value: false
#endif
mirror: always
# Whether anchor is kept selected.
- name: layout.selectanchor
type: bool
value: false
mirror: always
# Controls caret style and word-delete during text selection.
# 0: Use platform default
# 1: Caret moves and blinks as when there is no selection; word
# delete deselects the selection and then deletes word.
# 2: Caret moves to selection edge and is not visible during selection;
# word delete deletes the selection (Mac and Linux default).
# 3: Caret moves and blinks as when there is no selection; word delete
# deletes the selection.
# Windows default is 1 for word delete behavior, the rest as for 2.
- name: layout.selection.caret_style
type: int32_t
value: 0
mirror: always
# If layout.show_previous_page is true then during loading of a new page we
# will draw the previous page if the new page has painting suppressed.
- name: layout.show_previous_page
type: bool
value: true
mirror: always
# This will automatically enable inline spellchecking (if it is available) for
# editable elements in HTML.
# 0 = spellcheck nothing
# 1 = check multi-line controls [default]
# 2 = check multi/single line controls
- name: layout.spellcheckDefault
type: int32_t
value: 1
mirror: always
# Treat top level pages as always-active for the purpose of refresh driver
# throttling and such.
#
# Intended for testing automation and so forth.
- name: layout.testing.top-level-always-active
type: bool
value: false
mirror: always
# Pref to stop overlay scrollbars from fading out, for testing purposes.
- name: layout.testing.overlay-scrollbars.always-visible
type: bool
value: false
mirror: always
# Throttled frame rate, in frames per second.
- name: layout.throttled_frame_rate
type: uint32_t
value: 1
mirror: always
# Whether we should throttle in-process iframes in the active tab.
- name: layout.throttle_in_process_iframes
type: bool
value: true
mirror: always
- name: layout.lower_priority_refresh_driver_during_load
type: bool
value: true
mirror: always
# If > 0, nsRefreshDriver will keep ticking this amount of milliseconds after
# top level page load.
- name: layout.keep_ticking_after_load_ms
type: uint32_t
value: 1000
mirror: always
# Pref to control enabling scroll anchoring.
- name: layout.css.scroll-anchoring.enabled
type: bool
value: true
mirror: always
# Pref to control how many consecutive scroll-anchoring adjustments (since the
# most recent user scroll or timeout) we'll average, before we consider whether
# to automatically turn off scroll anchoring. When we hit this threshold, the
# actual decision to disable also depends on the
# min-average-adjustment-threshold pref, see below for more details.
#
# Zero disables the heuristic.
- name: layout.css.scroll-anchoring.max-consecutive-adjustments
type: uint32_t
value: 10
mirror: always
# Whether to reset counting the consecutive scroll-anchoring adjustments during
# running async scrolling by APZ.
- name: layout.css.scroll-anchoring.reset-heuristic-during-animation
type: bool
value: false
mirror: always
# The time after which we reset the max-consecutive-adjustments period, in
# milliseconds.
#
# This prevents sporadic back-and-forth scroll anchoring to trigger the
# max-consecutive-adjustments heuristic.
- name: layout.css.scroll-anchoring.max-consecutive-adjustments-timeout-ms
type: uint32_t
value: 500
mirror: always
# Pref to control whether we should disable scroll anchoring on a scroller
# where at least max-consecutive-adjustments have happened, and which the
# average adjustment ends up being less than this number, in CSS pixels.
#
# So, for example, given max-consecutive-adjustments=10 and
# min-average-adjustment-treshold=3, we'll block scroll anchoring if there have
# been 10 consecutive adjustments without a user scroll or more, and the
# average offset difference between them amount to less than 3 CSS pixels.
- name: layout.css.scroll-anchoring.min-average-adjustment-threshold
type: uint32_t
value: 2
mirror: always
# Pref to control disabling scroll anchoring suppression triggers, see
#
#
- name: layout.css.scroll-anchoring.suppressions.enabled
type: bool
value: true
mirror: always
- name: layout.css.scroll-anchoring.highlight
type: bool
value: false
mirror: always
# Pref to control whether we reselect scroll anchors if sub-optimal
#
- name: layout.css.scroll-anchoring.reselect-if-suboptimal
type: bool
value: true
mirror: always
# Are shared memory User Agent style sheets enabled?
- name: layout.css.shared-memory-ua-sheets.enabled
type: bool
value: true
mirror: always
# Is the CSS 'stretch' keyword enabled, for size-valued properties like 'width'
# and 'height'? (Note: this is unrelated to the 'stretch' value for the
# various alignment properties like 'align-self'; this pref has has
# no influence on the 'stretch' keyword for those alignment properties.)
- name: layout.css.stretch-size-keyword.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Is the '-webkit-fill-available' keyword enabled, as an alias for 'stretch'?
- name: layout.css.webkit-fill-available.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Is support for -webkit-line-clamp on regular blocks enabled?
- name: layout.css.webkit-line-clamp.block.enabled
type: bool
value: false
mirror: always
# Does webkit-line-clamp skip painting clamped lines?
- name: layout.css.webkit-line-clamp.skip-paint
type: bool
value: false
mirror: always
# Is support for the ::details-content pseudo-element enabled?
- name: layout.css.details-content.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Is 'content:none' supported on (non-pseudo) elements?
- name: layout.css.element-content-none.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether we want scrollbar-width: thin to behave as scrollbar-width: auto.
- name: layout.css.scrollbar-width-thin.disabled
type: RelaxedAtomicBool
value: false
mirror: always
# field-sizing CSS property
- name: layout.css.field-sizing.enabled
type: RelaxedAtomicBool
value: false
mirror: always
# Whether supports() conditions in @import is enabled
- name: layout.css.import-supports.enabled
type: RelaxedAtomicBool
value: true
mirror: always
rust: true
# Whether :-moz-broken is supported in content.
- name: layout.css.moz-broken.content.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
# Whether the modern ::slider-* pseudos are enabled.
- name: layout.css.modern-range-pseudos.enabled
type: RelaxedAtomicBool
value: false
mirror: always
rust: true
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