Got proprietary Nvidia drivers installed by Ubuntu itself, graphic card is recognized well by the system yet brightness control does not work when adjusted by either
F5/6 shortcut or by dragging brightness slider manually (keyboard shortcut triggers slider move as well, so it's heard by the system).
xrandr | grep " connected" | cut -f1 -d " " produces single output
xrandr --output DP-2 --brightness 0.7 does change the brightness.
Googled a lot, tried various options, neither works to me. What can I do to make it work when dragging the slider as well?