Tumbleweed snapshot 20180314 introduced two new start-up backgrounds to my computer: one for the grub menu, the other for the LightDM logon screen of my Cinnamon desktop.


I like the new grub menu, but am not wild about the new background for the LightDM logon menu. (And understand that developers can't please everyone.) I'd like to go minimalist and aim for an all-black background for my logon screen, perhaps by substituting all-black .jpgs for the current wallpaper .jpgs.


I believe that the relevant .jpg files are in:


/usr/share/wallpapers/openSUSEdefault/contents/images


Can I just create all-black .jpgs of the appropriate dimensions, copy them over to this directory as root and change permissions? Or is there something else that ought to be done?


I ask without first experimenting because I recall making a nice mess with a similar experiment with an Antergos Linux VM configured with LightDM. I didn't take notes, have forgotten the details of the mess, but it wasn't easy to fix.


If there's another setting I could change -- or another place I could put the customized wallpapers -- well, I'm all ears.