Created attachment 159913 [details]
Translucent pop-up in opaque panel

SUMMARY
When setting a panel to opaque it's pop-ups also become opaque, as expected. When restarting the plasma shell or rebooting, all pop-ups become translucent, even if they're in an opaque panel. This might relate to Bug 461459, but affects all pop-ups and is not fixed by opening a fullscreen window.


STEPS TO REPRODUCE
1. Add a panel and set it to opaque
2. Add a widget with a popup to the panel (e.g. digital clock or notifications)
3. Restart plasma shell or reboot the system

OBSERVED RESULT
After the reboot, all the pop-ups of the panel are translucent.

EXPECTED RESULT
Pop-ups should remain opaque

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.27.6
KDE Frameworks Version: 5.107.0
Qt Version: 5.15.10
Kernel Version: 6.3.9-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 3800X 8-Core Processor
Memory: 15,5 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 2080 SUPER/PCIe/SSE2