Comment 27 for bug 344228

This is fixed in g-c-c 3. We could get it in natty if someone works on backporting the change
Comments from gnome-control-center developer:
"We already do that for items that are remote, and will do it for items outside the Pictures directory or the stock items."

(If wallpaper is not in pictures directory, it will just be copied.)

Not a bug in firefox.