Email forward ends up in original topic

[JammyDodger]

Nice spot @Moin

@dachary

Here is how to reproduce the behavior on discourse 2.7.9:

• Create category A with mail a@example.com and category B with mail b@example.com
• Post a message in category A
• Reply via email and change the To: so that it is b@example.com
• The message ends up in category A, as a reply to the original message, instead of category B

This is presumably because the mail headers have information that allow discourse to know this mail was sent as a reply from the original message. So it has to make a choice: should this message be sent to:

I’ve just tried repro-ing this as well (a key difference seemed to be pressing ‘Reply’ and then manually changing the To address, rather than Forwarding), but mine ended up as a new topic in Category B again. Perhaps this does make it client specific? @artur Which are you using?