1893600 - CalDAV sync fails with "Assert failed: unexpected endBatch" on large batches

Status: UNCONFIRMED

(Calendar :: Provider: CalDAV, defect)

Description

[S. Seide]

Attachment: console-export-2024-4-25_12-9-21.txt

Steps to reproduce:

I use a CalDAV calendar which contains a lot of event series originally created on MS Exchange server. Our CalDAV server is not an Exchange.

From time to time (kinda randomly) events disappear in Thunderbird. The events are visible server side via its calendar server own Web-UI. Sometimes un-checking and checking again the calendar config setting "Offline support" brings back the events to Thunderbird, sometimes not.

But problem is probably the sync errors and events are missing depending on which sync batch they are...

Thunderbird 115.10.1 (64-Bit)
Linux amd64

Actual results:

On CalDAV sync error messages appear in the error console.
Events randomly disappear from the calendar in Thunderbird but remain in the calendar server side - they are just not shown in Thunderbird.

A log file with messages from the Thunderbird error console are attached to this report. Private information like mail addresses or links are changed.

Expected results:

No error messages on sync and all events are shown in the calendar the same as the server Web-UI does.