TLDR em1nos resolved an issue where new conversations were being created after each email reply by setting up a custom inbound domain in Postmark.
I had to setup the custom inbound domain in Postmark and add that domain to MAILER_INBOUND_EMAIL_DOMAIN. Now there's a replyto email on the outgoing emails, and the original issue with new conversations is no more.
em1nos
Mon, 13 Mar 2023 15:53:12 UTCI have an issue with the Email Inbox where new conversations are created after the first reply, since that changes the subject to add "Re: ". After an other reply a new conversation is created. There must be a way to fix this that I'm overlooking.