When setting up a new Debian Gnome it’s nice to make things look the way you want. Here’s a few changes I make to sort out my desktop.

Hide a User from the gdm3 Login Screen

This is how to hide a single user from the login screen – not hide all users. This is different to how it was done in earlier versions.

Create/edit a file with the users login name in /var/lib/AccountsService/users eg.

$ sudo vi /var/lib/AccountsService/users/myuser

Add the following or just change the SystemAccount value to true.

[User]
Language=
XSession=
SystemAccount=true

Put the gdm3 Login Screen on Your Preferred Monitor

When Debian gets installed sometimes my monitors appear the wrong way around and my primary display is monitor 2. In user mode I can change this easy enough, but the gdm login remains the wrong way around.

The process is straight forward. Move things around as your user and then copy your user config to the gdm user. This is Debian-gdm for Buster but may just be gdm on other flavours.

$ sudo cp ~/.config/monitors.xml ~Debian-gdm/.config/

and for Ubuntu

$ sudo cp ~/.config/monitors.xml ~gdm/.config/