---

sudo tee /usr/share/xsessions/ubuntu-xorg.desktop > /dev/null <<'EOF'
[Desktop Entry]
Name=Ubuntu on Xorg
Comment=This session logs you into Ubuntu using Xorg
Exec=env GNOME_SHELL_SESSION_MODE=ubuntu /usr/bin/gnome-session --session=ubuntu
TryExec=/usr/bin/gnome-shell
Type=Application
DesktopNames=ubuntu:GNOME
X-GDM-SessionRegisters=true
EOF