1981643 - [wpt-sync] Sync PR 54183 - Fix missing containing block in `css/css-anchor-position/anchor-center-fallback-transition-behavior.html`

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, task, P4)

Description

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

Sync web-platform-tests PR 54183 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/54183
Details from upstream follow.

Kiet Ho <[e-mail]> wrote:

Fix missing containing block in css/css-anchor-position/anchor-center-fallback-transition-behavior.html

In css/css-anchor-position/anchor-center-fallback-transition-behavior.html, there's no explicit containing block for anchor #a1 and anchor-positioned #t1, therefore the containing block of #a1 is the viewport and the fallback isn't used (because #t1 will be positioned within the containing block). Add an explicit containing block as parent of #a1 and #t1 to force the fallback behavior.

Tested on latest Safari Technology Preview. From the crbug that added the test, it is for a bug in Chrome 127 that was fixed in Chrome 132. I tried and the new test fails in Chromium 127.0.6533.0 (Developer Build) (arm64) and passes in Chromium 139.0.7258.0 (Developer Build) (arm64)

Comment 1

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

Pushed to try (stability) https://treeherder.mozilla.org/#/jobs?repo=try&revision=f746c8080fa537ddeb6067572ff1a952b538cdb5

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 338 tests

## Status Summary

### Firefox
`OK`  : 1[GitHub] 205[Gecko-linux2404-64-debug, Gecko-linux2404-64-opt, Gecko-windows11-32-24h2-debug, Gecko-windows11-32-24h2-opt, Gecko-windows11-64-24h2-debug, Gecko-windows11-64-24h2-opt] 206[Gecko-android-em-7.0-x86_64-lite-qr-opt-geckoview, Gecko-android-em-7.0-x86_64-qr-debug-geckoview, Gecko-android-em-7.0-x86_64-qr-opt-geckoview]
`PASS`: 25[Gecko-linux2204-64-wayland-debug, Gecko-linux2204-64-wayland-opt] 9529[Gecko-windows11-32-24h2-debug, Gecko-windows11-32-24h2-opt] 9549[Gecko-linux2404-64-debug, Gecko-linux2404-64-opt, Gecko-windows11-64-24h2-debug, Gecko-windows11-64-24h2-opt] 9559[Gecko-android-em-7.0-x86_64-lite-qr-opt-geckoview, Gecko-android-em-7.0-x86_64-qr-debug-geckoview, Gecko-android-em-7.0-x86_64-qr-opt-geckoview]
`FAIL`: 1[GitHub] 3916[Gecko-windows11-32-24h2-debug, Gecko-windows11-32-24h2-opt] 3996[Gecko-android-em-7.0-x86_64-lite-qr-opt-geckoview, Gecko-android-em-7.0-x86_64-qr-debug-geckoview, Gecko-android-em-7.0-x86_64-qr-opt-geckoview] 4003[Gecko-linux2404-64-debug, Gecko-linux2404-64-opt, Gecko-windows11-64-24h2-debug, Gecko-windows11-64-24h2-opt]

### Chrome
`OK`  : 1
`PASS`: 1

### Safari
`OK`  : 1
`PASS`: 1

## Links
[Gecko CI (Treeherder)](https://treeherder.mozilla.org/#/jobs?repo=try&revision=f746c8080fa537ddeb6067572ff1a952b538cdb5)
[GitHub PR Head](https://wpt.fyi/results/?sha=afb74467285097c97a794fbbd40f13ef93359365&label=pr_head)
[GitHub PR Base](https://wpt.fyi/results/?sha=afb74467285097c97a794fbbd40f13ef93359365&label=pr_base)

## Details

### Firefox-only Failures
* [/css/css-anchor-position/anchor-center-fallback-transition-behavior.html](https://wpt.live/css/css-anchor-position/anchor-center-fallback-transition-behavior.html) [[wpt.fyi](https://wpt.fyi/results/css/css-anchor-position/anchor-center-fallback-transition-behavior.html)]
  * anchor-center aligned bottom anchored element overflowing IMCB: `FAIL`

(See attachment for full changes)

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/c70df25a4167
https://hg.mozilla.org/integration/autoland/rev/dc87175a720c
[wpt PR 54183] - Fix missing containing block in `css/css-anchor-position/anchor-center-fallback-transition-behavior.html`, a=testonly

Comment 4

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/dc87175a720c