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I have a mail server with Postifx (and dovecot) setup, on which there is an alias address (say email@example.com) which forwards mail to my main email (firstname.lastname@example.org). This works fine, and all mail I send to email@example.com gets sent to firstname.lastname@example.org
However, when I reply to an email sent to email@example.com (using the gmail web interface), to the recipient, it looks like the mail came from firstname.lastname@example.org (or more specifically, the user of email@example.com, eg. Joe Bloggs).
Is there a way to make the email look like it came from firstname.lastname@example.org, or even just a custom name (such as Alias) rather than coming from Joe Bloggs < email@example.com >?