Ubuntu 20.04 Screen tearing

Screen tearing may happen when you change a display orientation to "Portrait Right" or "Portrait Left"

If you are using Intel's built-in graphic, you can try the combinations of following methods.

Method 1

Step 1. If you don't have the folder "/etc/X11/xorg.conf.d", create one.
Step 2. create the file 20-intel.confin the directory /etc/X11/xorg.conf.d/

content in 20-intel.conf

Section "Device"
    Identifier "Intel Graphics"
    Driver "intel"
    Option "TearFree" "true"
    Option "AccelMod"    "uxa"
    Option "DRI"         "3"
EndSection

and then reboot

Method 2

Try creating another file 20-intel-graphics.conf in the directory "/etc/X11/xorg.conf.d/"

content in the file

Section "Device"
    Identifier "Intel Graphics"
    Driver "intel"
    Option "TearFree" "true"
    Option "AccelMod"    "uxa"
    Option "DRI"         "3"
EndSection

and then reboot

Tips:
You can try playing the following options in method 1 and 2.

1. Try using either Option "AccelMod" "uxa" or Option "AccelMod" "sna" or none of them.
2. try using Option "TripleBuffer" "true" or not.
3. Try using Option "DRI" "3" or not

Remember to reboot after setting them.

Method 3

1. try removing the buggy package

sudo remove xserver-xorg-video-intel

and reboot

1. if that doesn't work, try reinstalling it.

sudo apt update
sudo install xserver-xorg-video-intel

My working settings (for your reference)

1. content in /etc/X11/xorg.conf.d/20-intel.conf and/etc/X11/xorg.conf.d/20-intel-graphics.conf

Section "Device"
    Identifier "Intel Graphics"
    Driver "intel"
    Option "TearFree" "true"
    Option "AccelMod"    "sna"
    Option "DRI"         "3"
    Option "TripleBuffer" "true"
EndSection

1. Reinstall xserver-xorg-video-intel

ref

• SO - Intel screen tearing - Ubuntu 18.04
• YT - Fix Screen Tearing in Linux
• YT - How To FIX Intel Screen Tearing In Linux