More generally. Filtering is Really important to me. What can be done to identify what's missing in ManageSieve and fill the gaps? This includes RegEx, Include, and encoded-character, header writing, etc.
As a newcomer to Roundcube and its code, I don't yet have a firm grasp on the integration points between Roundcube core, plugins, sieve/Pidgeonhole, Dovecot, and other components. It would REALLY help to find a clear roadmap in this area so that I can get into the code more quickly to understand what is there, what is not, and to make changes.
Thanks!
EDIT: Just found this gem:
https://kolabian.wordpress.com/2018/09/08/managesieve-editheader-extension/This world of RC and Sieve plugins is so mysterious. I wish there were one current/updated source of information. Is there a wiki somewhere? Should there be one?