Bug 210443

Summary:	Implement layer-based custom scrollbars
Product:	WebKit	Reporter:	Simon Fraser (smfr) <simon.fraser>
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 Simon Fraser (smfr) 2020-04-13 11:30:53 PDT

Custom scrollbars are currently just painted into the scroller's backing store. I'll fix that so they get painted into their own layers, but longer term we want to make a layer for the thumb, at least, so we can move it on the scrolling thread.

Comment 1 Radar WebKit Bug Importer 2020-04-13 11:31:19 PDT

<rdar://problem/61727923>