Desktop unusable after installation

[saivinob]

Welcome to the community @George_Guta.

Which graphics card do you have? Does the following issue similar to yours and the provides suggestion helps.

Ubuntu MATE 20.10 Display Problems

sorry if i posted this in the wrong place as it is my first time on this forum, and my english is not very good as i use translator. I currently use Ubuntu 20.10 and I decided to install MATE on it, when I switch to the MATE desktop the screen looks very choppy, I thought it was Ubuntu's error and I decided to try Ubuntu MATE and installing it brought me the same surprise, before I tried ubuntu mate 18.04 lts and it worked perfect for me, but with the most recent version no longer, and I don't…

http://ubuntuhandbook.org/index.php/2018/07/fix-screen-tearing-ubuntu-18-04-optimus-laptops/

Screen Tearing on Intel Graphics