I hadn't tried that one yet. But I tried it now.
I installed lightdm-gtk-greeter 201503290547~ubuntu15.04.1 from https://code.launchpad.net/~kalgasnik/+archive/ubuntu/lightdm-gtk-greeter-post-2.0.0 and removed the active-monitor option.
This fix solved the problem for me. After the reboot the login screen comes up right away.
I hadn't tried that one yet. But I tried it now.
I installed lightdm-gtk-greeter 201503290547~ ubuntu15. 04.1 from https:/ /code.launchpad .net/~kalgasnik /+archive/ ubuntu/ lightdm- gtk-greeter- post-2. 0.0
and removed the active-monitor option.
This fix solved the problem for me. After the reboot the login screen comes up right away.