I upgraded my system to Ubuntu 20.04 and since then I've had this problem: my system does not shut down or restart (either from the desktop or the terminal), instead the screen just freezes on the desktop screen.
I do not have much experience with Linux, so if anyone knows how to solve this problem, please give me detailed instructions on how to fix it. Thank you in advance!
sudo journalctl -b -1 -e
will show you the end of the previous boot's logs. Check for "timeout" messages. – waltinator Apr 22 '21 at 22:50