https://wpt.fyi/results/custom-state-pseudo-class/state-css-selector-shadow-dom.tentative.html the tests in this are slightly wrong due to some minor errors with the CSS. It uses the selector `:host:state(green)` which is invalid, it should be `:host(:state(green))`. The tests need to be tweaked for them to be valid.
https://github.com/WebKit/WebKit/pull/22222
Committed 272469@main (4dd84e9fa371): <https://commits.webkit.org/272469@main> Reviewed commits have been landed. Closing PR #22222 and removing active labels.
<rdar://problem/120069004>