Created attachment 391402 [details] add-remove-transition-diff legacy-animation-engine/compositing/transitions/add-remove-transition.html Description: This test is flaky failing on Mac wk1 Debug. The failures seem to be throughout the visible history, with the oldest matching diff that Im able to locate appearing on r254416. History: https://results.webkit.org/?suite=layout-tests&test=legacy-animation-engine%2Fcompositing%2Ftransitions%2Fadd-remove-transition.html&flavor=wk1&platform=mac&limit=50000&style=debug Diff: https://build.webkit.org/results/Apple-Catalina-Debug-WK1-Tests/r257132%20(2626)/legacy-animation-engine/compositing/transitions/add-remove-transition-diff.png
<rdar://problem/59669125>
I have marked this test as failing while this issue is occurring. https://trac.webkit.org/changeset/257136/webkit
I am able to reproduce the issue using r257133 with the command below. run-webkit-tests legacy-animation-engine/compositing/transitions/add-remove-transition.html --iterations 4000 --exit-after-n-failures 5 -f --force --debug -1 [17/4000] legacy-animation-engine/compositing/transitions/add-remove-transition.html failed unexpectedly (reference mismatch) [85/4000] legacy-animation-engine/compositing/transitions/add-remove-transition.html failed unexpectedly (reference mismatch) [542/4000] legacy-animation-engine/compositing/transitions/add-remove-transition.html failed unexpectedly (reference mismatch) [603/4000] legacy-animation-engine/compositing/transitions/add-remove-transition.html failed unexpectedly (reference mismatch) [888/4000] legacy-animation-engine/compositing/transitions/add-remove-transition.html failed unexpectedly (reference mismatch) Exiting early after 5 failures. 885 tests run. 880 tests ran as expected, 5 didn't (3115 didn't run):
This test is gone as of r258150, see bug 208815.