SamWhited [1] filed an orphan request for xml2rfc [2]:

People flagged that the package doesn't list its dependencies on 2019-12-23. The package is also out of date with no response from the owner.

[1] https://aur.archlinux.org/account/SamWhited/ [2] https://aur.archlinux.org/pkgbase/xml2rfc/