I've attached a reduced test case, but this is actually already tested by existing layout test compositing/geometry/clip.html which was baselined improperly. In the attached test case, you should see a small green box on top of the wheat-colored box. When the wheat box is not composited, it works properly. When it is composited, the composited layer is clamped to the element's border box, which is incorrect. Patch coming in a moment. By the way - It seems that layer-outline-expected.txt and layer-outline-horizontal-expected.txt may need to be rebaselined on other platforms after this change. Will it be OK to land this and expect someone else to rebaseline them?
Created attachment 205221 [details] Example of the CSS clip problem Example of the CSS clip problem. Small green div should be visible when correct. (try toggling the translateZ(0) property to make it un-composited, where it works correctly.)
Created attachment 205222 [details] Patch
Comment on attachment 205222 [details] Patch Attachment 205222 [details] did not pass win-ews (win): Output: http://webkit-queues.appspot.com/results/918724 New failing tests: fast/media/mq-transform-03.html fast/forms/search-event-delay.html fast/media/mq-transform-02.html platform/win/accessibility/multiple-select-element-role.html
Created attachment 205232 [details] Archive of layout-test-results from APPLE-EWS-2 for win-future The attached test failures were seen while running run-webkit-tests on the win-ews. Bot: APPLE-EWS-2 Port: win-future Platform: CYGWIN_NT-6.1-WOW64-1.7.20-0.266-5-3-i686-32bit
Seems to work now?
Comment on attachment 205222 [details] Patch Assuming that patches for review since 2013 are stale, r-
I am unable to reproduce this issue using attached test case (Example of ..) in Safari 15.6 on macOS 12.5 and it is showing "Green" above square showing clipped text and it matches with all other browsers (Chrome Canary 106 and Firefox Nightly 104), I think it got fixed along the way and this can be marked as "RESOLVED CONFIGURATION CHANGED". If I am testing incorrectly, please retest accordingly. Thanks!