In https://commits.webkit.org/267076@main I updated LayoutTests/imported/w3c/web-platform-tests/html/semantics/interactive-elements/the-details-element/toggleEvent.html but had inadvertently neglected to include some asserts for the details6 _“Calling open twice on 'details' fires only one toggle event”_ test.
Superseded by https://bugs.webkit.org/show_bug.cgi?id=260463. After further testing, I realized it’s not just that the asserts are missing — but also that the implementation isn’t setting the ToggleEvent oldState correctly.