Step 1: Check Available Sessions

List available sessions by running:

ls /usr/share/xsessions/

You might see output similar to this:

gnome-classic.desktop  gnome.desktop

If gnome-xorg.desktop isn’t available, install it:

sudo apt install gnome-session

Step 2: Set Default Session to X11

Edit or create your user’s session file:

sudo nano /var/lib/AccountsService/users/yourusername

Ensure it contains:

[User]
Session=gnome-xorg

Step 3: Configure Autologin on GDM3

Edit the GDM3 configuration:

sudo nano /etc/gdm3/daemon.conf

Add or uncomment these lines:

[daemon]
AutomaticLoginEnable=true
AutomaticLogin=yourusername

Step 4: Restart GDM3 or Reboot

Restart GDM3 immediately:

sudo systemctl restart gdm3

Or reboot your system:

sudo reboot

Verification

After rebooting, your system should automatically log in using the X11 session, removing the need to manually select “System X11” at login.