Login auth strip domain from username

[Ralph Seichter]

* David Pottage:

> is there a setting in dovecot that if it is given an email address as
> a login username it strips off the domain part [...]

You're probably looking for the 'username_format' configuration
parameter.

> If you know how to do that for postfix for sending email, then even
> better!

Assuming you need to configure more than a single MUA, you might find
https://gitlab.com/automx/automx2 useful.

-Ralph