SUMMARY
So I set my laptop screen brightness using the Battery and Brightness applet and it works. I can shutdown and reboot my laptop and the brightness is correct.

However, if I suspend or hibernate and then resume, the actual brightness would be at 100% while it still shows whatever I set it at in the applet. If I move the slider, the screen dims again.

If I resume and the screen is at 100% while the applet shows 50% and then reboot, the applet and screen would be both at 100%.

I'm not exactly sure if this is the fault of SDDM or Plasma 5.


STEPS TO REPRODUCE
1. Set brightness using Battery and Brightness applet
2. Suspend or hibernate
3. Resume

OBSERVED RESULT
Screen brightness is at 100% while the applet says otherwise.

EXPECTED RESULT
Screen brightness should be what was set in the applet, like how it does work with shutdown or reboot.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 6.4.12-arch1-1 (64-bit)
KDE Plasma Version: 5.27.7
KDE Frameworks Version: 5.109.0
Qt Version: 5.15.10

ADDITIONAL INFORMATION
Graphics Platform: X11
Display Manager: SDDM 0.20.0-2