This is free, open-source software used by organizations to manage electronic mailing lists and e-newsletters. It is written in Python and distributed under the GNU General Public License.
: Reviewers generally consider it one of the best mailing list managers available, though some "old school" versions were criticized for mailing out passwords in plaintext by default. 2. MailmanHQ (Gmail Productivity Plugin) Mailman Free Download
: The latest major update introduced a REST API, making it more modular and easier for developers to integrate into other applications. This is free, open-source software used by organizations
“mails out user passwords in plaintext every month by default. Insane. Old school mailing list software.” SourceForge On MailmanHQ (Gmail Plugin) This is free