Created attachment 468126 [details]
The diff

The test compositing/plugins/pdf/pdf-in-embed-rounded-border.html  has been failing on  Sonoma wk2  since its introduction at 269063@main.

HISTORY:
https://results.webkit.org/?suite=layout-tests&test=compositing%2Fplugins%2Fpdf%2Fpdf-in-embed.html

IMAGE DIFF:
See attachment

 
DIFF URL:
https://build.webkit.org/results/Apple-Sonoma-Release-AppleSilicon-WK2-Tests/269075@main%20(206)/compositing/plugins/pdf/pdf-in-embed-rounded-border-diff.png


REPRODUCIBILITY:

I was able to reproduce this issue on Sonoma ToT using the following commands:

python3 Tools/CISupport/download-built-product --platform=mac --debug 'https://s3-us-west-2.amazonaws.com/archives.webkit.org/mac-sonoma-x86_64 arm64-debug/269077@main.zip'

python3 Tools/CISupport/built-product-archive --platform=mac-sonoma --debug extract

python3 Tools/Scripts/run-webkit-tests --no-build --no-show-results --no-new-test-results --clobber-old-results --debug --results-directory layout-test-results --debug-rwt-logging --no-retry-failures compositing/plugins/pdf/pdf-in-embed-rounded-border.html

REGRESSION:

This test has been failing since it was introduced at 269063@main.