Allegedly, on or about 09 July 2017, Stephen Morris sent:
Sorry, I wasn't referring to TB's reply functionality as being a list issue, I agree with you that the functionality implemented by TB is stupid, and I'll see if I can post an issue on it on the post site that was discussing all the plugin support issues in Firefox and possibly TB that were originating with versions 52/53.
I'm wondering if that irritating behaviour can be bug reported as being non-RFC compliant. Thunderbird's behaviour is a serious screw-up.
At least Evolution handles it better: Decides you appear to be replying to a list, then asks you which way to reply. And gives you an option to make that a permanent choice (though I've no idea whether there's a way to unset that, later on).
People have been debating mailing list reply-to munging for years, but this behaviour causes far more problems than it allegedly fixes. For lists with a list reply address, the default reply should reply to that address, and an extra non-standard reply option ought to be for privately reply. For those peculiar lists that don't want public replies to the list, they won't have a reply-to header, and none of this nonsense is required.
For non-list mail, the reply-to should be adhered to, without stupidly offering a reply to the from header. The reply to is an override instruction, you're definitely supposed to only reply to the reply-to header.
e.g. You email a business about something, they respond to you with an email that's addressed so that your next reply goes back to where it needs to go, such as to a particular sales consultant, or to the general anyone in sales address.
I get the impression that this recent alleged improvement is from some dingbat who just doesn't understand email and lists.
What I was referring to as possibly being something the mailing list server was supplying was all the tags I listed above except for the reply-to tag, especially the list-subscribe and the list-unsubscribe tags. All those tags were in Rick's email just above what looked like possibly a certificate of some sort.
The info that Thunderbird, or any other mailer, is using to decide that a message is from a list rather than personal mail, is in the message headers, not what's typed in the message body.
Pretty much the last lot of headers just before the message starts:
X-Mailman-Version: 3.1.0 Precedence: list Reply-To: Community support for Fedora users users@lists.fedoraproject.org List-Id: Community support for Fedora users <users.lists.fedoraproject.org> Archived-At: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org/message/CTGE2LVKBQN22KBDIIFP2EWPWN3NYO32/ List-Archive: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org/ List-Help: mailto:users-request@lists.fedoraproject.org?subject=help List-Post: mailto:users@lists.fedoraproject.org List-Subscribe: mailto:users-join@lists.fedoraproject.org List-Unsubscribe: mailto:users-leave@lists.fedoraproject.org
The rest of the headers are just ordinary headers in any email. Pretty much, any of these headers that have *list* somewhere in them could be used by software to automatically identify it as list mail (the precedence header, the various List- headers).