2092291 - [wpt-sync] Sync PR 64557 - WebKit export of https://bugs.webkit.org/show_bug.cgi?id=192980

Status: RESOLVED FIXED

(Core :: Layout: Generated Content, Lists, and Counters, task, P4)

Description

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Sync web-platform-tests PR 64557 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/64557
Details from upstream follow.

Alan Baradlay <[e-mail]> wrote:

WebKit export of https://bugs.webkit.org/show_bug.cgi?id=192980

WebKit export from bug: [<!---->css-<!---->lists]<!----> Fix list marker issues related to line breaks and markers disappearance

<pre>
Keep the outside list marker at the list item and position it after layout

An outside list marker is currently reparented into whichever descendant holds
the list item's first line box, so an overflow, clip or transform on that
descendant makes the marker disappear or get clipped.

Keep the marker as the list item's first child instead, take it out of in-flow layout, and position it
after layout against the line it aligns with. Gated behind ListMarkerPositionedPostLayoutEnabled.

The line still has to make room for the marker, so line layout is handed its
layout bounds and grows the root inline box's layout bounds by them, which is
what a real marker inline level box would have contributed.

RenderListItem positions the marker once its in-flow content is laid out, since only then is every box between the line and
the list item in its final position, and adds the marker's overflow at that point.

WebKit-Bug: <a href="https://bugs.webkit.org/show_bug.cgi?id=192980">https://bugs.webkit.org/show_bug.cgi?id=192980</a>
WebKit-Canonical-Link: <a href="https://commits.webkit.org/318561@main">https://commits.webkit.org/318561@main</a>
</pre>

Comment 1

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Pushed to try (stability) https://treeherder.mozilla.org/jobs?repo=try&landoInstance=lando-prod-2025&landoCommitID=118965

Comment 2

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Attachment: Notable wpt changes

CI Results

Ran 11 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 971 tests

Status Summary

Firefox

OK : 129
PASS: 18[GitHub] 181[Gecko-linux2204-64-wayland-debug, Gecko-linux2204-64-wayland-opt] 2367[Gecko-windows11-32-25h2-debug, Gecko-windows11-32-25h2-opt] 2920[Gecko-android-em-14-x86_64-debug-geckoview] 2921[Gecko-android-em-14-x86_64-lite-opt-geckoview, Gecko-android-em-14-x86_64-opt-geckoview] 2925[Gecko-linux2404-64-debug] 2926[Gecko-linux2404-64-opt, Gecko-windows11-64-25h2-debug] 2927[Gecko-windows11-64-25h2-opt]
FAIL: 400[Gecko-windows11-32-25h2-debug, Gecko-windows11-32-25h2-opt] 501[Gecko-windows11-64-25h2-debug, Gecko-windows11-64-25h2-opt] 502[Gecko-linux2404-64-debug, Gecko-linux2404-64-opt] 503[Gecko-android-em-14-x86_64-debug-geckoview, Gecko-android-em-14-x86_64-lite-opt-geckoview, Gecko-android-em-14-x86_64-opt-geckoview]

Chrome

PASS: 18

Safari

PASS: 18

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Details

(See attachment for full changes)

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/aa5b618ce1fb
https://hg.mozilla.org/integration/autoland/rev/430daa9920c1
[wpt PR 64557] - WebKit export of https://bugs.webkit.org/show_bug.cgi?id=192980, a=testonly

Comment 4

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/430daa9920c1