Mailman does actually support email commands similar to those of Majordomo. This interface is provided mainly to provide compatibility for users who are familiar with Majordomo. It does provide at least one feature not available via the web interface, which is the ability for the list administrator to retrieve the complete list of subscribers. This is the who command.
In the notes below replace LISTNAME with the name your list to have the correct effect. You may request help for the Mailman email interface by sending an email to LISTNAMEfirstname.lastname@example.org containing a single line with the word "help". Be sure the send the email in plain text format. The reply from Mailman is similar to the example below.
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Last Updated: Friday January 18, 2019