Convergent builds its mail service on free software and sends its fixes upstream. Twelve pull requests accepted by SnappyMail and Tachyon: address book sync, message HTML sanitising, two-factor authentication, calendar invitations and LDAP directories.
Mail, calendars, contacts, tasks, notes, files and chat in one window, on infrastructure we run in Tunisia. The argument is not about software quality — it is about which court has jurisdiction.
Three Convergent fixes merged into Cyrus IMAP: a CalDAV server crash on free/busy requests, HTTP/2 responses truncated past 64 KB, and the version number still exposed in calendars despite serverinfo: off.