There's no "force reply" in the admin interface for Mailman but I have changed
reply_goes_to_list to be "Poster" which should do what you want - direct replies to become private.

Thanks,
Caleb


On 21/05/16 21:51, Holger Krekel wrote:
> With forced reply worst case is sending a private message to the group and k9/android cannot add the sender to the Adressbuch and there is no way to send the person a private mail, without forced reply a group message might only be sent to one member. Agreed, though, a reply-all duplicates mails in some clients. So we are on one level talking about UI deficiencies but what is left is accidental group messages... Happened to me and I am using email since centuries.
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