Hello,
I need to configure Mailcow so that it detects a certain regular expression in the email subject and sends a copy of the message to a dedicated mailbox, if the subject content matches. This must be configured globally for the whole mail domain.
I successfully configured this for incoming mail using Global Sieve Filter, but this filter does not work for outgoing mail and according to the several GitHub issues, it seems this is not supported by Mailcow. Is there a chance to configure Postfix directly to achieve this behavior?
I am using the latest 2025-03b Mailcow, which is running on my own virtual server. Therefore, am able to tweak the containers and their configuration directly.