Hey, surprise! This no longer works in Fedora 22! See my latest post, Disabling or re-enabling the Gnome 3 user list in Fedora 22.
Hey, so it’s a new version of Fedora with yet another upgrade of Gnome 3. Of course that means previous methods of disabling the trendy but security insensitive user list in the gdm login don’t work anymore. New solution below. IMPORTANT UPDATE on 16 Dec 2014.
In the last couple of Fedora releases you could turn off the user list for the gdm login screen by editing or adding /etc/dconf/db/gdm.d/01-local-settings under [/org/gnome/login-screen] to include “disable-user-list=true”, running dconf update and then restarting the gdm service. Well, doesn’t work with Fedora 21.
Note this procedure was updated on 16 Dec 2014 to add “sudo -u gdm” to the front of the gsettings command, ensuring that the change occurs to the gdm user’s copy of the dconf database AND to remind the user that gdm needs to be restarted to make the change effective.
sudo -u gdm gsettings set org.gnome.login-screen disable-user-list true
systemctl restart gdm
That’s it. Ignore all other proposed solutions past and present.