Comment 9 for bug 1391042

Hm. I wonder about the "sleep 30" call you added. What happens with it if you try to change the wallpaper several times quickly one after another?

    # Remove all Variety wallpapers, but the current one
    # Delay cleanup to wait for all changes otherwise you see artifacts
    sleep 30

I suspect the artifacts are caused because of some transition from the old to the new wallpaper? Can't the delay be small, e.g. 2 seconds, instead of 30?

Probably a better way to do this is to exclude both the old and new wallpaper from the deletion instead of putting a delay here.