Just changing the subject--maybe someone can make a more specific subject line.
On Tuesday, February 06, 2018 08:34:11 AM Vincent Lefevre wrote: > On 2018-02-05 18:01:08 +0000, Brian wrote: > > Now you have problems (or could have). The first problem is that the > > "duplicates" are not duplicates because the headers are different. The > > second problem is - which one do you wish to keep? The third problem > > (related to the second one) is the order in which the messages arrive. > > Is it the mailing list reply first or the Cc:? > > > > Users of mutt have it easy: > > > > send-hook . 'unmy_hdr Message-ID:' > > send-hook 'debian-user@lists\.debian\.org' 'my_hdr Message-ID:<`date > > +"%Y%m%d%H%M%S"`noccsple...@example.com>' > > > > A mail with NoCcsPlease in its In-Reply-To or References headers can > > only have had the mailing list mail as its source. However, the CC will > > not contain a List-ID: header. This makes it possible to distinguish > > between a list mail and a CC. Procmail recipes based on these two > > conditions can now file list mail with certainty and, if desired, delete > > CCs. > > If this is just a private reply, you will lose mail, unless the > procmail recipe also tests the To/Cc headers against the list address > (hoping the list server doesn't drop mail for some reason).