MarsSeed [1] filed a deletion request for blueshift-git [2]: GitHub repo is marked as archived; last commit is from 2017. [a]
No need to keep this VCS package. [a]: https://github.com/maandree/blueshift [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/blueshift-git/
