Bug 481161

SUMMARY
I've got a multi-monitor setup with one of my screens being an HDR screen (https://www.gigabyte.com/us/Monitor/M27Q-rev-20).
When switching to HDR mode on that HDR screen, the brightness starts flickering whenever firefox or thunderbird are open and focused on that screen (they don't need to be active, simple mouse hover is enough); haven't noticed this behavior with any other application, non-Qt apps included.


STEPS TO REPRODUCE
1. Set screen to HDR
2. Open up firefox or thunderbird
3. Move your mouse cursor over that screen

OBSERVED RESULT
Screen is constantly fglickering between the below-lowest brightness and the set brightness.

EXPECTED RESULT
Screen doesn't flicker at all.


SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 5.93.0
KDE Frameworks Version: 5.249.0
Qt Version: 6.7.0
Kernel Version: 6.7.4-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 3600 6-Core Processor
Memory: 15.5 GiB of RAM
Graphics Processor: AMD Radeon RX 6700 XT
Manufacturer: ASUS

ADDITIONAL INFORMATION
The screen flickers even when the brightness is set to the lowest possible SDR brightness in systemsettings.
When switching to HDR mode,, journalctl spams with constant message (about 10 times per second):
kwin_wayland[1237]: kwin_scene_opengl: 0x3: GL_INVALID_OPERATION in glUniformMatrix(matrix size mismatch)

Didn't notice it with any other GTK apps