Install cyrus-caldav by entering the following commands in the terminal:
sudo apt update sudo apt install cyrus-caldav
Description:
Cyrus mail system - CalDAV and CardDAV support
This package contains the CalDAV and CardDAV portion of the Cyrus IMAPd suite. . For more information, please see the cyrus-common package.
Homepage: http://www.cyrusimap.org/
Version: 2.5.10-3ubuntu1
Section: universe/mail