Public bug reported: I've run into the following behavior of mailman: I sent an email and CC-ed somebody@bla1.com, who also is a member of mailing list ml@bla2.com, which I also CC-ed: ... CC: somebody@bla1.com, ml@bla2.com ... When looking at the copy I got from the mailing list (I'm also a member), the email appeared as: ... CC: ml@bla2.com ... I saw this and thought I forgot to explicitly CC somebody@bla1.com, and had to go back to my sent box to find that I did indeed explicitly CC that address. So mailman is losing information when forwarding the email, and in my view this is a bug. The behavior is coupled to the member.receive_list_copy property (Subscription Option 'Avoid duplicate copies of messages?'), but I don't see why not sending a copy should mean removal from the CC-line in other copies. I suspect the behavior is due to the last 2 lines in this snippet from src/mailman/handlers/avoid_duplicates.py: ... if send_duplicate: msgdata.setdefault('add-dup-header', set()).add(r) newrecips.add(r) elif r in cc_addresses: del cc_addresses[r] ... ** Affects: mailman Importance: Undecided Status: New -- You received this bug notification because you are a member of Mailman Coders, which is subscribed to GNU Mailman. https://bugs.launchpad.net/bugs/1216960 Title: Address removed from CC-list To manage notifications about this bug go to: https://bugs.launchpad.net/mailman/+bug/1216960/+subscriptions