[Mailman-Users] Customize "From" when munging it for DMARC?

[Mark Sapiro]

On 08/04/2017 07:30 PM, Jordan Brown wrote:
> 
> What I'm objecting to is the fact that it hunts down *other* instances
> of the address in From and removes them (or perhaps replaces them with
> the Reply-To and then eliminates duplicates).  I think Reply-All should
> take {Reply-To, else From}, To, and CC, and reply to them.


I agree that what you think would be reasonable and what people
generally expect, but what RFC 5322 says is

      Note: Some mail applications have automatic reply commands that
      include the destination addresses of the original message in the
      destination addresses of the reply.  How those reply commands
      behave is implementation dependent and is beyond the scope of this
      document.  In particular, whether or not to include the original
      destination addresses when the original message had a "Reply-To:"
      field is not addressed here.

Which basically says that whatever the specific MUA does with reply-all
when there is a Reply-To: is not addressed by the standard and is up to
the implementer, so while you and I may not like the behavior of
outlook/hotmail in this case, we can't say it is non-compliant.

As an aside, you don't want to convince me that this behavior is wrong,
because you'd like me to do something in Mailman to make this reply-all
behavior work as expected, but I'm not interested in kludging Mailman to
accommodate broken MUAs.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan