Here is a quick fix for a weathered colours issue (the screen is too bright) with the latest X11 Intel driver (drm/i915) and some monitors with HDMI connection.
Step #1: Find your HDMI device name:
xrandr | grep HDMI | grep " connected" | cut -d" " -f1
This should print something like HDMI2 or HDMI3. If not, you are not using Intel driver or your HDMI device is not connected.
Step #2: Force your HDMI device to use full RGB colour range:
xrandr --output HDMI2 --set "Broadcast RGB" "Full"
Replace the “HDMI2” with your HDMI device name.
