I’ve been trying different distributions on my Thinkpad T480, via live USB. I like Ubuntu MATE the best, but unfortunately all of the available compositors seem to be broken. The default one causes jumpy window movement; the others have various problems, such as window movement lagging behind the mouse cursor, or choppy window resizing. Not one of them works correctly on my machine.
I can boot it up again and write up a more detailed report for each compositor if that would be helpful, but I guess my immediate questions are, if I am doing something obviously wrong, or if anybody else has had more luck running on a T480, or if anyone else has experienced the same thing.
Also FWIW this is all tested on an external monitor via USB-C, 3840 x 1600 at 60 Hz. I can test on the internal display if that would be helpful. Just let me know what information would be helpful to provide as a next step.