Looking for logging into the Lightdm Dual Screen site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Lightdm Dual Screen site. After that you can login as usual with your login credentials.
https://askubuntu.com/questions/234930/choose-lightdm-login-screen-location-in-multi-monitor-setup
https://forum.antergos.com/topic/6366/login-screen-on-wrong-monitor
https://ubuntu-mate.community/t/solved-multiple-display-16-04-loginscreen-placement/5456
https://forum.xfce.org/viewtopic.php%3Fid%3D9878
https://ubuntuforums.org/showthread.php%3Ft%3D2221275
https://www.reddit.com/r/Ubuntu/comments/7lj902/fix_multiple_monitors_order_on_login_screen_1710/
https://forum.manjaro.org/t/lightdm-login-dialog-is-displayed-on-the-wrong-monitor/11467
https://help.ubuntu.com/stable/ubuntu-help/display-dual-monitors.html
https://wiki.archlinux.org/index.php/LightDM
http://www.google.de/url?url=http://www.sudo-juice.com/lightdm-resolution/
https://answers.launchpad.net/lightdm/%2Bquestion/246547
https://bugs.launchpad.net/bugs/874241
https://linuxundich.de/gnu-linux/gdm-bei-dual-monitor-setup-auf-richtiges-display-schieben/