Mail::SPF::Mech::IP6(3pm) on Linux
The text ab0dfa116dd0, as Debian 10 (Buster), Debian 9 (Stretch) shipped it.
SPF record "ip6" mechanism class
The text ab0dfa116dd0, as Debian 10 (Buster), Debian 9 (Stretch) shipped it.
SPF record "ip6" mechanism class