same for me. this happened as i installed cursor ai and then installed fuse to execute it. have you found any solution to recover as before ?

This worked for me:

Switch to a Virtual Console (TTY)

Since the GUI isn’t working, switch to a terminal interface:

• Press Ctrl + Alt + F2 (or F3–F6)
• Log in with your username and password

Remove fuse from your system

sudo apt remove --purge fuse

Restart the display manager:

sudo systemctl restart gdm    # or lightdm, sddm, etc.

Reconfigure or Reinstall the Display Manager

If the display manager itself is broken:

sudo dpkg-reconfigure gdm3   # or lightdm

Or reinstall it:

sudo apt install --reinstall gdm3   # or lightdm

Reboot

After making your changes:

sudo reboot

If not still not working try the following

Check for a Valid Session File

List files in /usr/share/xsessions/:

ls -l /usr/share/xsessions/

Expected output (for GNOME):

gnome.desktop
ubuntu.desktop

If this directory is empty or missing GNOME:

sudo apt install ubuntu-gnome-desktop gnome-session

Check GNOME Session Binary

Check that the GNOME session command exists:

which gnome-session

Expected output:

/usr/bin/gnome-session

If it's missing:

sudo apt install gnome-session

Force Default Session

Try setting GNOME explicitly as the default session:

echo "gnome-session" > ~/.xsession
chmod +x ~/.xsession

Then reboot.

sudo reboot