User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0) Gecko/20100101 Firefox/88.0
Steps to reproduce:
When I create a new calendar-entry (CALDAV) inside thunderbird on my desktop-computer, everthing is fine. Thunderbird synchronizes all server-entries when a network-connection is established to the CALDAV-server (e.g. Nextcloud).
When I do the same on my Notebook with enabled "offline-support" for this calendar, thunderbird synchronizes also all server-entries from the CALDAV-server.
But after a few time the synchronization doesn't work... we get no error-report,.. but not all (new) calender-entries from the CALDAV-server are shown.
The only (really not good) solution is:
1.) verify that the network-connection to the CALDAV-server is established
2.) disable the "offline-support" for this calendar
3.) start manual synchronization
4.) enable the "offline-support" for this calendar
Unfortunately, I cannot ensure that I always have a network connection (for the notebook), so permanently deactivating offline support (as with my desktop pc) is not a solution.
After a few time the offline-synchronization of CALDAV-calendars doesn't work... without any error-report,...
Not all (new) calender-entries from the CALDAV-server are shown.
The start of a (manual) complete synchronization should also do exactly just that.
PS: Many users in several inzternet-forums describes exactly this wrong behavior...