https://drafts.csswg.org/css-cascade-6/#scope-syntax
<rdar://problem/118180841>
Pull request: https://github.com/WebKit/WebKit/pull/20243
Committed 270590@main (9ff407119919): <https://commits.webkit.org/270590@main> Reviewed commits have been landed. Closing PR #20243 and removing active labels.