crtc config fails when changing resolution with Xrandr from 4K

I used this guide to set a custom resolution via the video kernel parameter. This worked for me on Wayland, but I had to be very careful about the aspect ratio. My panel has 3:2, so I had to choose a resolution that has the same ratio.

The important bits from this guide are:

1. Add video=HDMI2:1920x1080@60 to your kernel parameters
2. Depending on your boot-manager do the necessary steps to enable your changes
3. Restart PC
4. Change the resolution using the GUI of your window manager

I would recommend a lower resolution that is exactly half of the native resolution and let the display do the interpolation (which is the case when using 1920x1080). This way fonts should still look ok on your 4K panel, because then each "virtual" pixel is directly mapped to 4 native pixels on your screen. If you have very good vision then you probably will notice blur if the panel's interpolation is not very good.