Multiseat is build-in in gdm3, so there is no configuration file.
So how to make a multiseat?
- you must use systemd
- remove old Xorg.conf multiseat files! (a Nvidia file is fine)
- run $ loginctl seat-status seat0
and find the keyboard, mouse and Gpu you want to use on your second seat
(the gpu must be a "master" device)
- run $ loginctl attach seat1 /sys/devices/pci.../.../.../your/mouse
for your mouse, keyboard and Gpu
log-off and log-on and gdm3 will appear on both screens
Success,
Floris
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