Bug 252999 - Unexpected result as paragraph z-index changes depending on CSS scale
Summary: Unexpected result as paragraph z-index changes depending on CSS scale
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: Compositing (show other bugs)
Version: Safari 16
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2023-02-27 09:26 PST by Adam Gamble
Modified: 2023-03-06 09:27 PST (History)
3 users (show)

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Description Adam Gamble 2023-02-27 09:26:30 PST 
Example case: https://jsfiddle.net/mdfs3tb0/

An outer div scales a fixed-size inner div (a 'canvas') which contains some elements positioned with translate().

Scaling past the bounds of the inner div will cause the z-index of the stacking order of the paragraph element to change.

This doesn't seem to happen in other browsers and seems unexpected.
Comment 1 Simon Fraser (smfr) 2023-02-28 12:38:27 PST 
I think this is about clipping and the overlap map; I recall another bug that's probably related.
Comment 2 Radar WebKit Bug Importer 2023-03-06 09:27:15 PST 
<rdar://problem/106292875>