I did this but when I restart my laptop and get to the login screen. The login-background changes back to my desktop-background after half a second.

How can i keep the Login-background for unlimited time?


sudo -i
xhost +SI:localuser:lightdm
su lightdm -s /bin/bash
gsettings set com.canonical.unity-greeter draw-user-backgrounds 'false'
gsettings set com.canonical.unity-greeter background 'path-to-image'
exit