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---
myst:
substitutions:
image1: |-
```{image} screenshot_button.png
:alt: Button to take screenshots of the entire page
:width: 20```
image2: |-
```{image} picker.png
:width: 20```
image3: |-
```{image} filter.png
:width: 20```
image4: |-
```{image} black_boxing.png
:width: 20```
image5: |-
```{image} import_button.png
:alt: Button to import a style sheet from the file system
:width: 20```
image6: |-
```{image} create_style_sheet_button.png
:alt: Button to create a new style sheet
:width: 20```
---
# Tips
## General
Screenshots:
- Entire page: Click the screenshot button ({{ image1 }} {ref}`needs to be enabled <tools-toolbox-extra-tools>` first).
- Viewport: Click the screenshot button ({{ image1 }}) in {ref}`Responsive Design Mode <responsive-design-mode-camera-button>`.
- Node: Right-click a node within the Inspector and click {ref}`"Screenshot Node" <taking-screenshots-of-an-element>`.
- Via {doc}`Web Console command <../web_console/helpers/index>`: `screenshot <filename.png> --fullpage`.
Settings:
- Choose between a {ref}`light and a dark theme <settings-themes>` for the developer tools.
- {ref}`Change the keyboard bindings <settings-editor-preferences>` to Vim, Emacs or Sublime Text if you're used to different shortcuts.
- Check or uncheck the different tools to enable or disable them. (There are more than the default tools!)
## Page Inspector
In the {ref}`markup view <page-inspector-ui-tour-html-pane>`:
- Press {kbd}`H` with a node selected to hide/show it.
- Press {kbd}`Backspace` or {kbd}`Del` with a node selected to delete it.
- {kbd}`Alt` + click on a node to expand or collapse it and all its descendants.
- Click on the last {ref}`breadcrumb button <page-inspector-how-to-examine-and-edit-html-breadcrumbs>` to scroll the selection into view in the inspector.
- Click the "ev" icon besides a node to {doc}`see all event listeners attached to it <../page_inspector/examine_event_listeners/index>`.
- Press {kbd}`S` with a node selected to see it in the page (same as right-click a node and click {ref}`Scroll Into View <page-inspector-how-to-examine-and-edit-scroll-into-view>`).
- Right-click a node and click {ref}`Use in Console <page-inspector-how-to-examine-and-edit-html-use-in-console>` to {doc}`command line <../web_console/the_command_line_interpreter/index>` as `tempN` variable.
When {ref}`selecting elements <page-inspector-select-element-button>`:
- {kbd}`Shift` + click to select an element but keep selecting (picker mode doesn't disengage).
- Use {kbd}`←`/{kbd}`→` to navigate to parents/children elements (if they're hard to select).
In the {ref}`rules view <page-inspector-ui-tour-rules-view>`:
- Click the inspector icon {{ image2 }} next to any selector to highlight all elements that match it.
- Click the inspector icon {{ image2 }} next to the `element{}` rule to lock the highlighter on the current element.
- Right-click any property and select "Show MDN Docs" to view the MDN docs for this property.
- Click on the filter icon {{ image3 }} next to an overridden property to {ref}`find which other property overrides it <page-inspector-how-to-examine-and-edit-css-overridden-declarations>`.
- Right-click on a name, value, or rule to copy anything from the name, the value, the declaration or the whole rule to your clipboard.
## Web Console
In all panels:
- {kbd}`Esc` opens the {doc}`split console <../web_console/split_console/index>`; useful when debugging, or inspecting nodes
In the {doc}`command line <../web_console/the_command_line_interpreter/index>`:
- {ref}`$0 <web_console_helpers_$0>` references the currently selected node.
- {ref}`$() <web_console_helpers_$>` is a shortcut to [document.querySelector()](https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelector)
- {ref}`$$() <web_console_helpers_$$>` returns an array with the results from [document.querySelectorAll()](https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelectorAll).
- {ref}`$$$() <web_console_helpers_$$$>` returns an array of all the elements matching the selector, even when they are in the shadow DOM.
- {ref}`copy <web-console-helpers-copy>` copies anything as a string.
- Right-click a node in the Inspector and click {ref}`Use in Console <page-inspector-how-to-examine-and-edit-html-use-in-console>` to create a {ref}`temp*N* <web-console-helpers-tempn>` variable for it.
- [console.table()](https://developer.mozilla.org/en-US/docs/Web/API/console/table) displays tabular data as table.
- {ref}`help <web-console-helpers-help>` opens the MDN page describing the available commands.
- `:screenshot <filename.png> --fullpage` saves a screenshot to your downloads directory using the optional file name. If no filename is included, the file name will be in this format:
```
Screen Shot date at time.png
```
The `--fullpage` parameter is optional. If you include it, the screenshot will be of the whole page, not just the section visible in the browser windows. The file name will have `-fullpage` appended to it as well. See {doc}`Web Console Helpers <../web_console/helpers/index>` for all parameters.
In the console output:
- Click on the inspector icon {{ image2 }} next to an element in the output to {ref}`select it within the Inspector <web-console-rich-output-highlighting-and-inspecting-dom-nodes>`.
- Check {ref}`"Enable persistent logs" <settings-common-preferences>` in the settings to keep logged messages from before even after navigation.
- Check {ref}`"Enable timestamps" <settings-web-console>` in the settings to show timestamps besides the logged messages.
## Debugger
- Skip JavaScript libraries in debugging sessions via the black box icon {{ image4 }}.
- Press {kbd}`Ctrl` + {kbd}`Alt` + {kbd}`F` to search in all scripts.
- Press {kbd}`Ctrl` + {kbd}`D` to search for a function definition.
- Press {kbd}`Ctrl` + {kbd}`L` to go to a specific line.
## Style Editor
- The black box icon {{ image4 }} in the style sheet pane toggles the visibility of a style sheet.
- Click an {ref}`@media rule <style-editor-the-at-rules-sidebar>` to apply it in {doc}`Responsive Design Mode <../responsive_design_mode/index>`.
- Click the import button {{ image5 }} to import a style sheet or the create button {{ image6 }} to create a new one.
- Click the options button in the {ref}`style sheet pane <style-editor-the-style-sheet-pane>` and click {ref}`"Show original sources" <style-editor-source-map-support>` to toggle the display of CSS preprocessor files.
## Network Monitor
- Click the request summary to {doc}`compare performance of cache vs. no-cache page loading <../network_monitor/performance_analysis/index>`.
- When a request is selected click {ref}`"Edit and Resend" <network-monitor-request-list-edit-and-resend>` to modify its headers and send it again.
- Check {ref}`"enable persistent logs" <settings-common-preferences>` in the settings to keep requests from before even after navigation.
- Hover the {ref}`"js" icon within the "Cause" column <request-list-requst-list-cause-column>` to see the JavaScript stack trace, which caused the request.
- Check {ref}`"Disable HTTP Cache (when toolbox is open)" <settings-advanced-settings>` in the settings to disable the network cache while debugging network issues.
## Storage Inspector
- Right-click the column headers to open a menu allowing to toggle the display of the columns.
- Right-click an entry and click "Delete *name*" to delete it or "Delete All" to delete all entries.
- Select an entry to see the parsed value of it in the sidebar.