[Mailman-Users] Assistance with altering reply-to behaviours and DMARC

[Stephen J. Turnbull]

Mark writes:

 > Is there any other code in the standard mailman where the reply-to
 > is populated with the original sender?  I realise fully aware that
 > the version of mailman I have here isn't supported, or released,
 > and other bugs may have been introduced.

In standard Mailman >= 2.1.18-1 (more or less) there are two places.
I guess the one you found is the unconditional "from_is_list" setting
in CookHeaders.py; sorry, I misled you because I was under them
impression that all such changes would take place in CookHeaders.  In
2.1.20, there's another, more complex path which involves checking
dmarc_moderation_action in SpamDetect.py, deciding which headers to
munge in CookHeaders.py:change_header(), and actually doing the work
in WrapMessage.py.

I don't have 2.1.18-1 to hand, and I'm not sure that is the version
that was backported anyway, so it's hard to be sure what you'd need to
change.  Probably searching for "dmarc" in SpamDetect and WrapMessage,
and "change_header" in CookHeaders, will allow you to figure out how
the backport works.