Hi,
Today I saw 3rd case, so I guess the is real an issue on F31 .
1 - VirtualBox
https://bugzilla.rpmfusion.org/show_bug.cgi?id=5383
filed a bug in fedora
https://bugzilla.redhat.com/show_bug.cgi?id=1758724
The maintainer said that the reason for the crash is the hard coded
dependencies on X11 API, without forcing the Qt's backend to be the one
it depends on.
2 - smplayer
https://bugzilla.rpmfusion.org/show_bug.cgi?id=5438
3 - Today mixxx commit
https://pkgs.rpmfusion.org/cgit/free/mixxx.git/commit/?id=709069aaddacf11...
Use XCB instead of the default Qt Wayland platform adapter
https://bugs.launchpad.net/mixxx/+bug/1850729
https://fedoraproject.org/wiki/Changes/Qt_Wayland_By_Default_On_Gnome
--
Sérgio M. B.