Bug 283115 – REGRESSION (283298@main): GitHub.com: checks run have condensed UI and not expanded to area in STP207 compared to Safari 18.1

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Ahmad Saleem]

Created attachment 473225 [details]
Safari 18.1 vs STP207

Hi Team,

While going through GitHub PR's, I stumbled upon an layout issue.

Baseline: You need to be logged in.

*** Steps to Reproduce ***

1) Go to GitHub PR with failing tests (e.g., https://github.com/WebKit/WebKit/pull/19308)
^ I deliberately picked old PR, which does not have chances to be updated.

2) Look at `checks` area

*** Expected Result ***
Scrollbar should be next to container and not condensed

*** Actual Result ***

Scrollbar is not next to container and is condensed.

___

Just raising so we can fix it.

[Radar WebKit Bug Importer]

<rdar://problem/139882323>

[alan]

Created attachment 473229 [details]
Test reduction

[alan]

This is a very edge case of when we've got a float box at a certain y position that our box needs to avoid but this float is actually has zero margin box width (non-zero border box with large enough negative margin) so our box is not constrained by it at all.

[alan]

Created attachment 473233 [details]
[fast-cq]Patch

[EWS]

Committed 286637@main (4e3542612b56): <https://commits.webkit.org/286637@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 473233 [details].

[EWS]

Committed 283286.492@safari-7620-branch (33b2af279a87): <https://commits.webkit.org/283286.492@safari-7620-branch>

Reviewed commits have been landed. Closing PR #2299 and removing active labels.