I'm happy to announce a new list for Mailman 3 users and others interested in Mailman 3. This list is running on a new Mailman 3 installation at lists.mailman3.org.
The list's posting address is firstname.lastname@example.org.
The list's info page is https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ and its archives are at https://email@example.com/.
You can subscribe by email by sending a blank message to firstname.lastname@example.org and responding to the resulting confirmation request. You can also subscribe by going to the info page at https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/, logging in and subscribing.
Log in offers three options. There are Google and Facebook OAuth2 login links on the log in page to log in with a Google or Facebook account, and there is a 'Login by email' link to login via Persona with any address you register and confirm with Persona.
This is a new installation of Mailman 3 so there are still kinks to work out, and any issues can be discussed on the list or reported to the trackers at https://gitlab.com/mailman/postorius/issues, https://gitlab.com/mailman/hyperkitty/issues or https://gitlab.com/mailman/mailman/issues as appropriate.