Ubuntu 20.04 graphics driver problem [duplicate]
I had the similar problem and on my research found that it's intel new graphic update problem. I was able to solve my issue by issuing following commands on my terminal.
sudo apt purge xserver-xorg-video-intel
After issuing the command, it is recommended that you restart your pc but logout and log back in may also work fine. I hope this will be able to solve your problem. If you face any issue please let me know.