Bug 238323 – [GTK4] UI process hang when opening HTML select elements (combo boxes)

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKitGTK

[Michael Catanzaro]

I'm seeing very frequent UI process hangs when attempting to report bugs on this Bugzilla. The problem occurs when clicking on the select elements (combo boxes) next to the "Hardware" or "OS" fields when reporting bugs. (You'll notice I've left those at Unspecified to avoid triggering this bug.) The entire UI process hangs when clicking on the element.

The bug is not 100% reproducible, but you should be able to trigger it if you try a few times.

[Carlos Garcia Campos]

Is this GTK4 only?

[Michael Catanzaro]

Yes, this never happens with GTK 3.

[Michael Catanzaro]

Another reproducer: try to give r+ to a patch on this Bugzilla.

[Michael Catanzaro]

Checking with gdb, it looks like the UI process is just calling poll() when this happens, and hovering buttons in the Epiphany header bar triggers animations, so I don't think this is a traditional hang or deadlock where the UI process is totally unresponsive. However, it's not just web views that are busted: the buttons in the header bar don't do anything, so GTK itself is somehow broken.

[Alice Mikhaylenko]

This looks like yet another instance of the bug behind https://gitlab.gnome.org/GNOME/gtk/-/issues/2877 or the one where gtk4-demo sidebar items remain pressed after double clicking

Basically, input is completely busted when another surface is spawned or destroyed in the middle of an event sequence - e.g. a click.

[Alice Mikhaylenko]

Ok, so I can still reproduce it so apparently that wasn't it.

[Alice Mikhaylenko]

*** Bug 240922 has been marked as a duplicate of this bug. ***

[Alice Mikhaylenko]

Pull request: https://github.com/WebKit/WebKit/pull/4095

[EWS]

Committed 254237@main (4e07bc369ad1): <https://commits.webkit.org/254237@main>

Reviewed commits have been landed. Closing PR #4095 and removing active labels.