Michael Hillmdhillca@gmail.com2012David Kingamigadave@amigadave.com2014Petr Kovarpknbe@volny.cz2014Make users type in their username on the login screen.Disable the user list
You can disable the user list shown on the login screen by setting the
org.gnome.login-screen.disable-user-list GSettings key.
When the user list is disabled, users need to type their user name and
password at the prompt to log in.
Set the org.gnome.login-screen.disable-user-list key
Create a gdm keyfile for machine-wide settings in
/etc/dconf/db/gdm.d/00-login-screen:
[org/gnome/login-screen]
# Do not show the user list
disable-user-list=true