On Sat, Feb 14, 2026 at 11:55:07AM +0000, Crystal Kolipe via Mutt-dev wrote:
On Sat, Feb 14, 2026 at 11:35:03AM +0800, Kevin J. McCarthy wrote:Now that we're back to applying patches from the mailing list, I have a question about technique.The Mutt mailing lists have "dmarc_moderation_action" set to "Munge From", which means when a sender's domain has a DMARC Reject/Quarantine Policy set, the mailing list rewrites the From address. Without this, a fair number of receivers bounce the message, which ends up unsubscribing them eventually.If the senders are including valid DKIM headers, and the MX of the subscribers is capable of verifying them, then the messages should pass DMARC Reject.
It's been a while. At the time, it may have been that the return-path header or another such header that is modified by Mailman, was signed by various senders' DKIM. I didn't realize the problem until I got a very large number of admin bounce emails and mass unsubscribes started happening.
However, it looks like at some point subsequent to that, OSUOSL added filters:
DMARC-Filter: OpenDMARC Filter v1.4.2 smtp4.osuosl.org 62BE640969 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org 62BE640969
Perhaps the problem is no longer present.I will try turning off of the munging for the mutt-dev mailing list right after I send this, and let's see what happens. Crystal and Alex, if things go silent after this email, please let me know and I'll try something else.
-- Kevin J. McCarthy GPG Fingerprint: 8975 A9B3 3AA3 7910 385C 5308 ADEF 7684 8031 6BDA
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