I'd like to parse incoming mail with custom script. Something which would be easily done with
man aliases(5) for real users or with procmail for vitual users.
But on my system is is plesk and setup is: virtual_transport = plesk_virtual, thus I cannot put configure it as virtual_transport = procmail.
What is plesk_virtual anyway, where are the configuration files, documentation? ("plesk_virtual" site:https://docs.plesk.com/ finds nothing, Mail doc neither).