Stalwart Mail Server strictly validates JSCalendar task properties on CalendarEvent/set and rejects updates containing top-level progressUpdated with invalidProperties (RFC 8984 §5.2.2 only defined progressUpdated on Participant objects, obsoleted in JSCalendar 2.0).
- Omit progressUpdated from toggleTaskComplete in stores/task-store.ts
- Remove progressUpdated from CALENDAR_TASK_PROPERTIES in lib/jmap/client.ts
- Defensively strip progressUpdated in updateCalendarEvent and createCalendarTask
- Make progressUpdated optional in CalendarTask interface
- Add unit tests for task-store and JMAP client task methods