This fix is courtesy of @oops.
If you are like me and prefer the username to be available in a drop-down on lightdm Here’s what you need to do to allow a username drop-down to appear:
$ cat /usr/share/lightdm/lightdm.conf.d/02_my_user.conf # Debian specific defaults # # - use lightdm-greeter session greeter, points to the etc-alternatives managed # greeter # - hide users list by default, we don't want to expose them # - use Debian specific session wrapper, to gain support for # /etc/X11/Xsession.d scripts [Seat:*] greeter-session=lightdm-greeter #greeter-hide-users=true greeter-hide-users=false session-wrapper=/etc/X11/Xsession