Service workers running on the main thread should use the main VM. This makes life easier for injected bundle clients and there is no strong reason to use a separate VM since VMs are mainly used for thread safety / isolation.
Created attachment 441247 [details] Patch
Comment on attachment 441247 [details] Patch r=me
Found 30 new test failures: fast/css-custom-paint/animate.html, fast/css-custom-paint/arguments.html, fast/css-custom-paint/constructor.html, fast/css-custom-paint/delay-repaint.html, fast/css-custom-paint/delay.html, fast/css-custom-paint/image.html, fast/css-custom-paint/leaks.html, fast/css-custom-paint/multiple-worklets-isolation.html, fast/css-custom-paint/multiple-worklets.html, http/tests/media/hls/video-cookie.html ...
Created attachment 441295 [details] Patch
Committed r284226 (243035@main): <https://commits.webkit.org/243035@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 441295 [details].
<rdar://problem/84285075>