Looking for logging into the Ubuntu 18.04 Screen Background 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 Ubuntu 18.04 Screen Background site. After that you can login as usual with your login credentials.
https://vitux.com/how-to-change-login-lock-screen-background-in-ubuntu/
https://askubuntu.com/questions/1042942/how-to-change-ubuntu-budgie-login-screen-background
https://www.ostechnix.com/how-to-change-gdm-login-screen-background-in-ubuntu/
http://ubuntuhandbook.org/index.php/2017/10/change-login-screen-background-ubuntu-17-10/
https://help.ubuntu.com/stable/ubuntu-help/look-background.html.en
http://krackhack.blogspot.com/2018/05/changing-purple-background-on-ubuntu.html
https://ubuntuforums.org/showthread.php?t=2400921
https://github.com/juhaku/loginized
https://www.reddit.com/r/Ubuntu/comments/9vae3x/1810_change_login_screen_colors/
https://ubuntu-mate.community/t/background-in-login-wont-change-um-18-04/16732
https://c-nergy.be/blog/?p=11550
https://www.omgubuntu.co.uk/2018/05/gnome-shell-lock-screen-redesign
https://gitlab.gnome.org/larsa/gdm3-background