Bug 95288

Summary: Incorrect stacking order for element with position fixed and computed z-index auto
Product: WebKit Reporter: christophf
Component: CSSAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: ahmad.saleem792, ap, bfulgham, paulirish, rniwa, simon.fraser, yves.vangoethem, zalan
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
URL: http://jsfiddle.net/hT6c9/11/
Attachments:
Description Flags
screenshot1 (expected) and screenshot2 (observed) none

Description christophf 2012-08-28 22:54:24 PDT 
Created attachment 161137 [details]
screenshot1 (expected) and screenshot2 (observed)

Expected [screenshot 1]
Observed [screenshot 2]

From http://www.w3.org/TR/CSS21/visuren.html#propdef-z-index 

"The root element forms the root stacking context. Other stacking contexts are generated by any positioned element (including relatively positioned elements) having a computed value of 'z-index' other than 'auto'"

reproduces for versions
537.8 (@126787) and
537.4 (@126115) 
but not
537.1 (@125733)
Comment 1 Yves Van Goethem 2012-09-10 10:25:15 PDT 
I can not confirm this behavior in the latest WebKit nightly build for OS X (Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/537.10+ (KHTML, like Gecko) Version/6.0 Safari/536.25)
The nightly build works as expected as does every other browser.

Chrome 22 beta and the latest Chromium nightly (23.0.1263.0 (155710)) still fails on rendering the given testcase correctly.
Comment 3 Ahmad Saleem 2022-07-24 07:00:49 PDT 
I am unable to reproduce this bug in Safari 15.6 on macOS 12.5 using attached JSFiddle and all browsers (Chrome Canary 106 and Firefox Nightly 104) match with Safari as well. I think it was fixed along the way and can be closed as "RESOLVED CONFIGURATION CHANGED". If I am testing incorrectly, please ignore my comment. Thanks!