Secondary screen freezes after changing refresh rate

[Forpli]

Xorg has problems with different refresh rates. You could try this solution if you want to set up different refresh rates in Xorg:

Refresh Rate

You could take a look here: "First add those 2 lines to /etc/environment: CLUTTER_DEFAULT_FPS=144 #Put your refresh rate __GL_SYNC_DISPLAY_DEVICE=DP-0 #Mine was DP-0 Then launch Nvidia X Server settings by typing "nvidia-settings" and then disable "Allow Flipping" in the OpenGL menu. To apply after every reboot, you just need to launch the "nvidia-settings" menu to apply the settings."

Here is another link:

https://www.reddit.com/r/linuxhardware/comments/mht7kn/workaround_for_multiple_monitors_with_different/