Some mails bounce with status=bounced (SMTPUTF8 is required, but was not offered by host mail.xxxxxxx.net[/var/run/dovecot/lmtp])

Turns out postfix advertises SMTPUTF8 support, but dovecot LMTP cannot handle SMTPUTF8 at the moment, therefore postfix bounces the mails (see this stackexchange question).

imho we should disable advertising SMTPUTF8 support in postfix, but the only concern is that this could break existing setups which use postfix only for sending SMTPUTF8 mails.

What do you think?