Situation: I receive an email from "[email protected]" and I click 'reply' "[email protected]" has a user with a preferred email address: "[email protected]" Question: How do I get the 'To:' field of the reply to auto-populate with "[email protected]" instead of "[email protected]"? Explanation: I am looking for a way to transform the recipient e-mail address that is auto populated in the "To:" field when I click reply. Ideally, I would manually enter the new recipient information only once and Thunderbird would remember and do the transformation every time thereafter. Sort of like a custom auto-correct. So if Thunderbird sees "[email protected]", it 'auto-corrects' it to "[email protected]" Any ideas?