Bug 85647 - box-shadow causes overlay scrollbars to be in the wrong position when element is composited
Summary: box-shadow causes overlay scrollbars to be in the wrong position when element...
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: New Bugs (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Simon Fraser (smfr)
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2012-05-04 11:49 PDT by Thomas Fuchs
Modified: 2012-09-07 17:49 PDT (History)
7 users (show)

See Also:

Attachments
reduced test case (1.29 KB, text/html)
2012-05-04 11:49 PDT, Thomas Fuchs 		no flags Details
Patch (9.00 KB, patch)
2012-09-07 14:47 PDT, Simon Fraser (smfr) 		jamesr: review+
Details | Formatted Diff | Diff
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Description Thomas Fuchs 2012-05-04 11:49:56 PDT 
Created attachment 140290 [details]
reduced test case

Using CSS `box-shadow` on an element that shows scrollbars (overflow: auto) can cause the scrollbars of the element to appear in the wrong position. A related problem is that in the provided reduced test case, enabling hardware acceleration for the parent element causes the child's scrollbars to disappear completely.

This problem happens in both the latest release version of Chrome and in the Safari 5.2 beta (I could not test on Safari 5.1, but it is likely to be a problem there too).
Comment 1 Radar WebKit Bug Importer 2012-05-04 11:52:16 PDT 
<rdar://problem/11386222>
Comment 2 Simon Fraser (smfr) 2012-05-04 11:57:40 PDT 
I can't find any code that positions the scrollbar layers in RenderLayerBacking. Weird.
Comment 3 Simon Fraser (smfr) 2012-09-07 14:47:51 PDT 
Created attachment 162874 [details]
Patch
Comment 4 Simon Fraser (smfr) 2012-09-07 17:49:00 PDT 
http://trac.webkit.org/changeset/127943