An implicit-root IntersectionObserver should be able to have targets in multiple windows, and observe the intersection of each of them with their window's viewport.
Created attachment 354579 [details] Patch
Attachment 354579 [details] did not pass style-queue: ERROR: Source/WebCore/ChangeLog:8: You should remove the 'No new tests' and either add and list tests, or explain why no new tests were possible. [changelog/nonewtests] [5] Total errors found: 1 in 7 files If any of these errors are false positives, please file a bug against check-webkit-style.
Created attachment 354580 [details] Patch
Comment on attachment 354579 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=354579&action=review > Source/WebCore/ChangeLog:8 > + No new tests (OOPS!). Fix this.
(In reply to Simon Fraser (smfr) from comment #4) > Comment on attachment 354579 [details] > Patch > > View in context: > https://bugs.webkit.org/attachment.cgi?id=354579&action=review > > > Source/WebCore/ChangeLog:8 > > + No new tests (OOPS!). > > Fix this. Removed that line in the latest patch since there's a web platform test that covers this (and passes after this patch). Is that sufficient test coverage or do you think we need more?
@Ali: What's the status of this? Are you still working on this patch?
(In reply to Frédéric Wang (:fredw) from comment #6) > @Ali: What's the status of this? Are you still working on this patch? This got dropped in the lead-up to IntersectionObserver being enabled by default, since it seemed like a risky change relative to the edge-case that it handles. The patch should mostly still apply, I expect.
Comment on attachment 354580 [details] Patch This has been requesting review for more than one year. If this is still needed, please rebase and re-request review.