Integration with webmail


I’m in a “degoogling” process and Nextcloud is what I found to be the best to replace Google Apps. The Nextcloud Mail app however is unusable from my point of view, so I’m using an external webmail for this. As I have a personal e-mail server, I tried SOGO, Rainloop and now I’m using Roundcube.

Roundcube is great for e-mail and I can access Nextcloud Contacts from it. But I couldn’t integrate Nextcloud Calendar so I can accept event invitations from e-mails and automatically add it to my calendar. SOGO has a built-in calendar, but I can’t use Nextcloud calendars in it and the e-mail usability isn’t as good as Roundcube’s.

Does anyone knows how can I achieve this with Roundcube or, maybe, SOGO? I know I can use SOGO’s caldav server instead but I prefer concentrating as much as possible on Nexcloud.

Thanks in advance!