Wayland is designed to replace the X11 server, which has been the standard display server used for decades on Linux. Although it is more modern and lighter than X11, not all apps are compatible with Wayland yet, as they were designed to work with X11. This is why X11 is still widely used today.
So here’s how to turn it off:
Open the custom.conf file with a text editor in administrator mode:
For Ubuntu, Debian:
sudo nano /etc/gdm3/custom.conf
For Fedora:
sudo nano /etc/gdm/custom.conf
Modify the line that contains #WaylandEnable=false by removing the # character at the beginning:
WaylandEnable=false
Save the file (Ctrl^O) then quit the nano editor (Ctrl^X).
Restart Linux. Wayland will be disabled.