TestWebKitAPI.WKUserContentController.UserStyleSheetAffectingOnlySpecificWebViewSharedConfiguration is a flaky timeout on macOS bots https://results.webkit.org/?suite=api-tests&test=TestWebKitAPI.WKUserContentController.UserStyleSheetAffectingOnlySpecificWebViewSharedConfiguration
<rdar://problem/61229832>
This test was added four weeks ago with: Add an SPI to allow UserStyleSheet injection to target a specific WKWebView https://trac.webkit.org/changeset/257870/webkit
Looking at historical results, I think that this test has been a flaky timeout since it was added.
Created attachment 395565 [details] Patch
Committed r259569: <https://trac.webkit.org/changeset/259569>