Q:

What's the replacement for lightdm service in Lubuntu 20.04

I used to do
sudo service lightdm restart

under Lubuntu 18.04 LTS to solve blackscreen problems sometimes. Now that lightdm is gone in Lubuntu 20.04 LTS,
what is the service equivalent to lightdm above that I can use in 20.04?

A:

It is sddm

sddm is the default display manager that shows up when you first log
  in to Lubuntu or logout or choose to another session. There is no
  graphical application to do this currently.

Lubuntu Manual

