Huawei MateView on QubesOS

If your display is configured @ 3840 x 2160, then you might not be satisfied with the lack of 1.5 million pixels on the screen or the occasional blinking /blacking of the screen

Go to Dom0 and write:

cvt 3840 2560 30

xrandr –newmode <output after modeline >

xrandr –addmode DP-1 –mode 3840x2560_30.00

xrandr –output DP-1 –mode 3840x2560_30.00

If you are using HDMI-1 instead of DP-1 us that. Check with following command

xrandr <enter>