I have a virtualmin / webmin server setup. Some domains don't want to receive emails directly to their domains. So I have setup a server-side forward to their Gmail adresses.
The forwarding works, and the emails are delivered to the Gmail mail boxes. However, the FROM address in the email headers are the same as the original sender. This results in the forwarded messages (sometimes) are flagged as spam by some mail providers.
Is there a Postfix or virtualmin setting that 'replaces' the FROM header with the email address of the domain that did the forwarding? Just like the behaviour that normal email clients (like Thunderbird) do. In Thunderbird, when I receive a message that I want to forward, I right-click and select 'forward' from the dropdown and it automatically sets MY own email address in the 'From' field.