Re: Subject Line Prefix Missing

To drive this more Off-Topic than it already is...

> Mailing list software for decades inserts unique headers for filtering
> purpose. "List-Id" is AFAICT the most common one, which is also used
> by GNU mailman. It has been specified in 2001 in RFC2919

Even non-Mailinglist software, e.g. GitHub, EBay, Deutsche Bahn, are
supplying custom List-Id headers for separate topics. In case of GitHub
one can use List-Id headers to automatically separate mails for
different repositories without looking at the content or Subject.

Cheers
Andrej