case ${ACTION} in
post)
	cat <<_EOF
==========================================================================
To make lightdm work a greeter package must be installed:

	lightdm-gtk-greeter: for a GTK+ greeter
	lightdm-gtk3-greeter: for a GTK+3 greeter

To start lightdm: 'systemctl start lightdm.service'.
==========================================================================
_EOF
	;;
esac