How to Switch from SDDM to GDM3 Display Manager on Ubuntu 18.04 LTS?
i) SDDM is the Display Manager for KDE.
ii) GDM3 is the Gnome Display Manager, it is the default Display Manager for Gnome Desktop.
Step 1: Right click on the desktop, and then click on 'open terminal.'
Step 2: After that, run the command below:-
sudo dpkg-reconfigure gdm3
Step 3: Restart your ubuntu system, you will see the change in login screen.
Step 4: You can check whether gdm service is running or not, by command below:-
systemctl status gdm.service
It's done
Thanks for watching, please like and subscribe
==============================================
https://www.facebook.com/HowtoTutorialsByAmit/