Default configuration doesn't show any wallpaper

[ids1024]

The cosmic-bg package doesn't install a configuration file, and it prints Config file error, falling back to defaults: Failed to get find config file (it probably shouldn't show an "error" if it's expected to not have a config on default installs).

It looks like the default uses CosmicBgImgSource::Wallpapers, but $HOME/Pictures/Wallpapers doesn't exist or have wallpapers by default.

I guess this is configuration is really a placeholder until we establish how wallpaper configuration should work, but in any case it should something from /usr/share/backgrounds/pop.