My monitor setup is a 1920x1080 on the left and a 3840x2160 monitor on the right, running an NVIDIA driver.
My problem is everything is very small on the 4K display and normal sized on the Full HD one. If I change the scaling in Display settings everything on the Full HD one is too big.
So I did some research and tried to get Wayland to work, but I have an NVIDIA GPU so it wouldn't work and I didn't want to install the nouveau drivers since I heard those have bad performance.
I read that this problem could be fixed with
xrandr, and I tried a lot of commands too but I never got it to work. One time I was really close to having it work with
xrandr but than after a restart, everything was reset again.