Bug 264763

Summary: [macOS] Scrolling occurs on `pointer-events: none` container when child that does react to scroll events cannot scroll anymore
Product: WebKit Reporter: Abrar Rahman Protyasha <a_protyasha>
Component: ScrollingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: a_protyasha, m_dubet, simon.fraser, webkit-bug-importer
Priority: P1 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
See Also: https://bugs.webkit.org/show_bug.cgi?id=258255
Attachments:
Description Flags
Test case
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Description Abrar Rahman Protyasha 2023-11-13 12:00:00 PST 
In 270094@main, we fixed the case where a scroll container has `pointer-event:none` but some child still reacts to scroll events, but it looks like we're still scrolling the ancestor container when the scrollable child cannot react to scroll events anymore (i.e. we've scrolled to the bottom of the child). Repro video attached. Test case is on https://pages.github.pie.apple.com/ada-cannon/misc/scroll-menu-nohax.html.

This is not necessarily a regression because this was our default (and only) behavior before 270094@main, but now we're doing the right thing initially and _still_ have this buggy behavior.
Comment 1 Radar WebKit Bug Importer 2023-11-13 12:00:46 PST 
<rdar://problem/118347784>
Comment 2 Abrar Rahman Protyasha 2023-11-13 12:07:20 PST 
Created attachment 468583 [details]
Test case
Comment 3 Abrar Rahman Protyasha 2023-11-13 12:07:56 PST 
Comment on attachment 468583 [details]
Test case

Attaching the test case as an HTML file because the linked page is not accessible for non-Apple folks.
Comment 4 Abrar Rahman Protyasha 2023-11-13 12:11:06 PST 
Created attachment 468584 [details]
Repro video