How do I return to default wallpaper on login screen in LightDM?

With the change to 12.04 came the new feature of having the login screen matching the selected user's wallpaper. It's a cool feature, but not for everyone. I'd like to go the other way and go back to having a default login screen (lightDM) wallpaper that doesn't change to match the selected User's wallpaper. Is this possible?

Solution 1:

If you're using one of the stock wallpapers I don't know of a way to do it, but I don't see why you'd want to hide any of those, as they're pretty innocuous :)

If it's an image in a user's home directory, you could try changing it so it can only be read by that particular user: right-click on the file, select Properties, then Permissions, and set "Access" for both Group and World to "None". The login manager should then be unable to read the image and will show a default image instead.

Solution 2:

You might try downloading/installing Ubuntu Tweak. There is an option to select a wallpaper for the login screen (Tweaks>Login Settings). If your custom-selected image doesn't display afterwards, you may need to sudo copy it into the /usr/share/backgrounds directory, then right-click change the permissions to match the default wallpapers.

I hope that works like what you've got in mind. Take care.