Louis [1] filed a orphan request for ubuntu-wallpapers [2]:

The maintainer hasn't reacted on out of date fag made back in November '15.

I also sent him an email on in the beginning of April without getting an reaction.

[1] https://aur.archlinux.org/account/Louis/ [2] https://aur.archlinux.org/pkgbase/ubuntu-wallpapers/