When an email is received by Postfix using SMTPUTF8 and the recipient domain is a Unicode internationalized domain, it was failing to be delivered (bouncing with 'relay access denied') because our users and aliases tables only store ASCII (IDNA) forms of internationalized domains. In this commit, domain maps are added to the auto_aliases table from the Unicode form of each mail domain to its IDNA form, if those forms are different. The Postfix domains query is updated to look at the auto_aliases table now as well, since it is the only table with Unicode forms of the mail domains.
However, mail delivery is still not working since the Dovecot LMTP server does not support SMTPUTF8, and mail still bounces but with an error that SMTPUTF8 is not supported.
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