I installed a fresh NixOS on LVM on a L490i7 connected to a Lenovo Pro Dock and (one or two) PD2700U (4K).
It happens a lot that the display freezes and after 1 or 2 seconds the mouse appears on a different position (due to movement while the display is frozen).
Other strange behavior appears with the cursor which doubles the size (e.g. in falkon browser when coming from the top display and reaching a browser tab).
I tried to stop animations (not yet fully successful) and would like to get some hints what let NixOS behave with issues regarding the display.