Bug 249278

Summary:	Don't paint empty scrollbar parts
Product:	WebKit	Reporter:	Ahmad Saleem <ahmad.saleem792>
Component:	Scrolling	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	simon.fraser, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	Safari Technology Preview
Hardware:	Unspecified
OS:	Unspecified

Description Ahmad Saleem 2022-12-13 16:46:10 PST

Hi Team,

This might be partial merge of following Blink commit:

Blink Commit - https://chromium.googlesource.com/chromium/blink/+/8991628a5345bdc95e6063aac05a3d71a43ca173

I have seen at least two cases (during triaging old bugs), where we paint black bar in place of scrollbar and when we resize then we get scrollbar or the area (black) get removed.

Webkit GitHub Source - https://github.com/WebKit/WebKit/blob/403e78eb6ddb81c1319cca7045b09199474573ed/Source/WebCore/rendering/RenderLayerScrollableArea.cpp#L1476 & https://github.com/WebKit/WebKit/blob/403e78eb6ddb81c1319cca7045b09199474573ed/Source/WebCore/rendering/RenderLayerScrollableArea.cpp#L1421

Just wanted to raise this bug and get input. It does not have any dedicated test case.

If without test, it is OK to merge then I am happy to do PR.

Thanks!

Comment 1 Radar WebKit Bug Importer 2022-12-20 16:47:14 PST

<rdar://problem/103576749>