SUMMARY If i select Okular, openning documents set external monitor brightness to %100 everytime and this is very annoying in dark places. I use only external monitor connected to my Mesa Intel® UHD Graphics 620 (WHL GT2) with HDMI, and use Wayland Session, not use internal laptop monitor. Gnome Wayland Session, Okular 1.11.1 or other Snap or Flatpaks with same issue. STEPS TO REPRODUCE 1. Connect external monitor from HDMI interface. 2. Open a PDF with Okular. OBSERVED RESULT External monitor brightness increase to %100 EXPECTED RESULT External monitor brightness remain same. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Ubuntu 20.04.1 KDE Plasma Version: KDE Frameworks Version: 5.74.0 Qt Version: Qt 5.15.1 ADDITIONAL INFORMATION Gnome Wayland Session, Okular 1.11.1 or other Snap or Flatpaks with same issue.
Ther is no problem in the X.org Session.
Sorry, there are problem with X11 too. But Problem is sometimes trgiggered, but sometimes not triggered.
Okular doesn't change the screen brightness. Maybe there is a setting in Powerdevil to force a different brightness for presentation mode.
There is no bug anymore so i marking this as "WORKSFORME"