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# device grid. An overflow clip sits flush with the inner edge of its
# container's painted border box, so rounding it outward spills a whole device
# row of scrolled content over that border.
#
# The red strip is the "border": rows 20..30 inclusive. The clip-chain node
# (mirroring an overflow:hidden container) starts at 30.7, just past the centre
# of row 30, so row 30 lies outside it and must stay red. The Ahem block spans
# device rows 28..67, i.e. it is scrolled well past the clip - exactly the case
# where an outward-rounded clip (-> 30.0) admits row 30 and paints it black.
#
# It must be an ancestor clip, not the text item's own clip-rect: Gecko's text
# leaf clip is the item bounds inflated by 1px (TextDrawTarget::Reinitialize),
# so a leaf clip never crops a run. Compared against the same scene with the
# clip on the pixel boundary at 31.0, which excludes row 30 under any policy.
root:
items:
- type: rect
bounds: [0, 0, 200, 120]
color: white
- type: rect
bounds: [0, 20, 120, 11]
color: red
- type: clip
id: 2
bounds: [0, 30.7, 120, 60]
- type: clip-chain
id: 3
clips: [2]
- bounds: [0, 0, 120, 120]
glyphs: [55]
offsets: [10, 60]
size: 40
color: [0, 0, 0, 1]
font: "Ahem.ttf"
clip-chain: 3