SoGo (link) is an amazing groupware that is e.g. part of the mailcow ecosystem. However, fully self-hosting an email solution is a bit of a struggle to put it mildly, so it would be absolutely amazing to get a single container to act as a groupware server but only access existing (e.g., Gmail) email accounts via smtp/imap.
SoGo can do this pretty much exactly like NextCloud Mail / Contacts / Calendar, but offers a much more refined and clean UI.
Currently, there is no SoGo docker container and the installation is quite involved. For the ideal small-ish linuxserver container, it should use sane defaults that allow to connect to existing email accounts via imap/smtp and to use SoGo as CalDav / CardDav server.
Thanks!