I'm getting a sync error on the first launch of OneCalendar in Windows 11 when attempting to connect with iCloud calendar. In the same calendar session, if I force a second sync, there is no error, and the calendar seems to function normally. I have attached the trace, with my specific calendar info replaced by pound signs.
Also, if I close OneCalendar and re-launch, the sync error does not occur. After that, it appears that the sync error occurs on every other launch of the calendar.