To Disable Guest-User from LightDm-LoginScreen
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# vi /etc/lightdm/lightdm.conf.d/50-myconfig.conf
[SeatDefaults]
allow-guest=false
#
To Enable Manual Login Screen on LightDm-LoginScreen
=======================================
# vi /etc/lightdm/lightdm.conf.d/50-myconfig.conf
[SeatDefaults]
allow-guest=false
greeter-hide-users=true
greeter-show-manual-login=true
#
To Enable AutoLogin on LightDm-LoginScreen
=======================================
# vi /etc/lightdm/lightdm.conf.d/50-myconfig.conf
[SeatDefaults]
allow-guest=false
greeter-hide-users=true
greeter-show-manual-login=true
autologin-user=ubadmin
#
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