Thunderbird error while accepting invitations

Nextcloud version: 27.0.2.1
Operating system: Ubuntu 22.04.3
Apache version: 2.4.52
PHP version: 8.2.8
Thunderbird: 115.1.1

I have Nextcloud calendars synced with Thunderbird via CalDav.
This is working fine so far.
When I invite someone for an event and someone is accepting it via
Thunderbird, Thunderbird throws the error “80004005”.
The error only occurs if the calendar and the event are not yet synced.
If I manually sync before there is no error.
“Offline support” is on in thunderbird

Basically the same error is described here: Error when accepting a calendar invite on Thunderbird

I guess Thunderbird + Nextcloud is the most used combination. So almost everyone should have this problem!!!? Anyone knows a solution? Is this working fine for someone?

Steps to replicate it:

  1. Sync calendars in thunderbird
  2. Invite to an event
  3. Accept invite before sync
  4. Get error 80004005

image

The output of your Nextcloud log in Admin > Logging:
Nothing relevant!

config.php:

This might help: