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+Mailman3 Core Docker Image
+==========================
+
+To run this container, you need a valid configuration at
+`/opt/mailman/mailman.cfg` on your host. When you spawn off this container, you
+must mount `/opt/mailman` to the container. Mailman's `var` directory will also
+be stored here so that it can persist across different sessions and containers.
+
+It is not advised to run multiple mailman processes on the same host sharing the
+same `/opt/mailman` directory as this will almost certainly be dangerous.