Created attachment 186386 [details]
screenshot of the broken popup

SUMMARY
Items inside the popup don't show up, instead it's empty with a few accent-coloured pixels(?)

STEPS TO REPRODUCE
1. Add a Quicklaunch widget
2. Enable popup in its settings 
3. Add launchers to it and drag them into the popup

OBSERVED RESULT
A right-to-left loading bar shows up and the pixels(?) appear but nothing besides them. Popup changes size when adding more items as if they're being added just not displayed correctly. It can be "scrolled" up and down by holding left click.

EXPECTED RESULT
Added launchers appear and can be used in the popup

SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 43 (Kinoite)
KDE Plasma Version: 6.5.1
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Kernel Version: 6.17.5-cachyos1.lto.fc43.x86_64 (64-bit)
Graphics Platform: Wayland

ADDITIONAL INFORMATION
Happens both if the widget is on the desktop or in a panel. Also affected a widget with items already in it that'd worked fine on 6.4.5. None of the other widget settings seem to affect it. Dragging items into it can be really difficult as it closes itself, easier if dragging from another quick launch widget bug is the same. If the popup is opened, then I click on the desktop it'll stay open and on top of all other windows until manually closed with the arrow button.