@Mark: I am really sorry for the delayed responses, but this is a very low frequency list. I have subscribed to the list using a non-Microsoft address to see the outcome.
The mails does indeed contain 'X-Mailman' headers.
X-Mailman-Rule-Hits:nonmember-moderation X-Mailman-Rule-Misses:dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation
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