Re: master 42596bd 2/6: Little improvements in rmail.el. Recognize encryped override headers.

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Wed, 12 May 2021 14:17:45 +0200
> Cc: Richard Stallman <rms@gnu.org>
> 
> rms@gnu.org (Richard M. Stallman) writes:
> 
> > +    ;; Debbugs sometimes adds `[External] :'; if that happened,
> > +    ;; delete everything up thru there.  Empirically, that deletion makes
> > +    ;; the Subject match the other messages in the thread.
> 
> This is not accurate -- it's just Drew that insists on adding that
> string to his subjects.  I find it pretty odd to add general code to
> Emacs to handle a single person's Subject mangling.

Drew might be a single person, but he tends to flood the Emacs mailing
lists with a lot of messages carrying this addition.  Rmail's
threading is based on comparing their Subject lines, and Rmail already
has quite a few heuristics whose purpose is to clean up the Subject
line to that end.  I see nothing wrong with adding one more
heuristics; the problem hits me as well.