I just bought a laptop from TUXEDO Computers and installed Qubes OS on it. (This is also my first time using Qubes OS.)
Problem: Xfce(?) recognises the
[fn+F9] key strokes as the correct key strokes for brightness adjustment: It displays the brightness label and the current brightness bar next to it in a notification. However the actual screen brightness is not adjusted. The screen always has the same amount of uncomfortable brightness even after a reboot. Also one weird thing happens: each time I press
[fn+F9] a new instance of the “[Dom0] Display” appears.
Attempts to fix the problem:
I searched this forum and the internet, but could not find anything suitable to my specific device. I tried different things, e. g. switching to KDE as suggested in one place, but had no success.
On the webpage of TUXEDO Computers there are instructions for fixing issues with non functional adjustment of screen brightness: https://www.tuxedocomputers.com/en/Infos/Help-Support/Instructions/Brightness-for-120-Hz-and-144-Hz-displays_1.tuxedo
The fix works on systems with grub and is applied by editing
/etc/default/grub and adding device specific parameters to the grub command line. However I do not know if this can be applied to the different infrastructure of the Qubes OS Dom0 system.
Questions: Does anyone know from my descripton of symptoms what the problem could be and how it could be solved? Or does anyone know a way to apply the suggested fix on the web page of TUXEDO computers to the Dom0 system?