Confirm page for new subscriptions will need to send auth token to mailman core
Once the templates are available in Mailman core, one of them will be the template for the confirmation email that goes out when someone new is subscribed to a list that wants an email confirmation before the subscription can be completed.
The "click to confirm" link will send the user to a url in Postorius. This means Postorius needs a confirmation page passes the confirmation token in the URL to mailman core (and gives the user some helpful message indicating that the process is complete)
As of this writing, this it blocked pending the template branch getting merged in Mailman Core.