Enable root user in Ubuntu 20.04

Step 1: Login into your account and open terminal

Step 2: Type the following command to setup password for root account

sudo passwd root

Step 3: Open file /etc/pam.d/gdm-password

sudo nano /etc/pam.d/gdm-password

Step 4: Comment out the following line by placing # infront of it

#auth    required    pam_succeed_if.so user != root quiet_success

Step 5: sudo gedit /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf

Step 6: At the end of the file append greeter-show-manual–login = true

Step 7: Reboot the server