I've set in lightdm.conf these 2 settings (under the Seat:* section) and the autologin doesn't work. It still ask me for user and password
autologin-user=user
autologin-user-timeout=0
I've tried with this setting in addition, but it still doesn't work
user-session=default
In addition, the checkbox "Don't ask for password on login" is disabled and not checked.