[MlMt] List membership disabled -- excessive bounces?

[Benny Kjær Nielsen]

On 19 May 2025, at 14:48, Bill Cole wrote:

> On 2025-05-19 at 05:22:42 UTC-0400 (Mon, 19 May 2025 11:22:42 +0200)
> Benny Kjær Nielsen <mailmate at lists.freron.com>
> is rumored to have said:
>
>> I'm not sure if this indicates that all senders on the mailing list have to have DKIM configured for their domains now? This is not the case for the From address involved.
>
> I believe it only requires that all mailing lists using Mailman that touch the body to "Munge All" From addresses and re-sign messages.

Currently, this only happens for emails from domains with DMARC enabled and a reject policy. Even if I did this for all emails from domains with DMARC enabled then I don't think it would solve this problem. There would still be emails with a DKIM signature from a non-DMARC domain. My server would either need to strip the DKIM-headers or munge/resign these emails as well, but I don't see an option for that in Mailman (2.x).

I might have gotten this totally wrong, but I'm pretty sure the latest Gmail problem is related to a failed DKIM signature. (Even the emails with no DKIM signature might eventually become a problem.)

It seems to me that I should perhaps just munge the From header in all emails.

> Using the "Wrap" option is arguably the technically best approach but it is the least user-friendly because not all MUAs handle the message/rfc822 content-type adeptly.

I have the unique advantage of knowing that most users of the mailing list will be using MailMate to view the emails. I could add features handling this gracefully. This might be better going forward although I don't know if such atypical emails would be seen as more or less spammy by the algorithms out there.

-- 
Benny