Consider this question on how to change the login picture.
I cannot in fact follow none of the answers posted there.
But even before re-asking a question like "how to change the login image" I would like to know:
Should the login use the desktop picture? Should it change when the desktop one is changed and so be the same? Because in my case it is NOT.
I use to change the desktop wallpaper by going to Settings - Desktop - Wallpaper or just right clicking an image 'Set as desktop background' in Files.
My login screen is (was) this one no matter what desktop wallpaper I selected:
That is, until I followed this answer and now the login image is missing: black.
The folder /usr/share/backgrounds looks like so:
Notice the added images at the end and the symlink that was created following the linked answer.
But they are not accessible from Settings:
I found a fix to the lost login image:
Selected one of the default wallpapers that are visible from Settings - Desktop - Wallpaper
Then changed desktop wallpaper again: in this way the login has an image: the one before the last change of the desktop image.
