Bug 231340 added support for CSSImportRule.layerName (https://drafts.csswg.org/css-cascade-5/#extensions-to-cssimportrule-interface) However, it doesn't exist when running WebKitGTK minibrowser, e.g. Tools/Scripts/run-minibrowser --gtk 'http://wpt.live/css/css-cascade/layer-rules-cssom.html' fails some tests. This also affects wpt.fyi, lowering WebKitGTK's score for interop-2022-cascade: https://wpt.fyi/results/css/css-cascade/layer-rules-cssom.html?label=master&label=experimental&product=webkitgtk&aligned&q=label%3Ainterop-2022-cascade I guess it's because WebKitGTK uses CMake, and CSSImportRule+Layer.idl was not included in CMakeLists.txt
Created attachment 449696 [details] Patch
Created attachment 449709 [details] Patch
Created attachment 449714 [details] Patch
Didn't notice that css/css-cascade/idlharness.html is also passing now.
Committed r288404 (246295@main): <https://commits.webkit.org/246295@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 449714 [details].
<rdar://problem/87926717>