compositing/z-order/rebuild-sibling-of-layer-with-foreground-layer.html Is a flakey image failure on both BigSur Wk1 and Wk2 arm64 debug and release. History: https://results.webkit.org/?suite=layout-tests&test=compositing%2Fz-order%2Frebuild-sibling-of-layer-with-foreground-layer.html Image Failure: https://build.webkit.org/results/Apple-BigSur-Release-AppleSilicon-WK1-Tests/r274479%20(343)/compositing/z-order/rebuild-sibling-of-layer-with-foreground-layer-diff.png
<rdar://problem/75485025>
Created attachment 423365 [details] Expected
Created attachment 423366 [details] Actual
Created attachment 423369 [details] Diff
Unable to reproduce due to not having access to Apple Silicon Mac.
Updated test expectations: https://trac.webkit.org/changeset/274517/webkit
Created attachment 423403 [details] Patch
https://trac.webkit.org/changeset/274524/webkit