Sorry, this is a misunderstanding on my part.

I saw

"Google accounts have been fixed and can now set up again properly",
.... "And a few bugs and common issues have been fixed, too."

and was of the opinion that something was fixed with the online accounts. That's why I tried "Generic CALDAV" again after a long time. I was pleased to see that this feature no longer crashes like it did in previous versions. However, appointments are still not synchronized.

@Mikaelb, I know the script solution and have used it for several months.

But, it no longer works for me with the OTA-21 RC.

In the terminal I start as part of a bash script :

/usr/bin/syncevolution kalender

and get errors with OTA-21 now. That's new! At the moment the calendars cannot be used.

The system message is

status = 20010
error = error code from SyncEvolution error parsing config file (local, status 20010): kalender: backend not supported by any of the backend modules (syncxmlrpc, syncsqlite, syncqtcontacts, syncmaemocal, synckcalextended, syncfile, syncecal, syncebook, syncdav, syncactivesync , platformgnome) or not correctly configured (backend! 3dselect backend databaseFormat! 3d syncFormat! 3d)
start = 1641012600, 2022-01-01 05:50:00 +0100
end = 1641012600, 2022-01-01 05:50:00 +0100

Edit :
Status 20010 could be : 20010 Error parsing XML config file

I flashed an old Xperia X Compact with a fresh OTA 16. The original battery (old, I know) has to be charged in the evening after a day of idling. For a 2700 mAh battery, that's disappointing. Is it worth buying a new battery and what runtime can I expect? Does anyone have any experience?

Generic CALDAV? with Nexus 5

I am using a local CALDAV server with Ubuntu Mate (radicale server) and cannot sync my calendars. Radicale works as it should. I have been using my own calendar server successfully with all devices for years.

What I do....
I add an internet calendar and select Generic CALDAV. After entering the local address ("192.168.x.x: 5232/username/") my 4 calendars and 1 address book are found and displayed. All 4 calendars are marked for viewing.
Furthermore, the account has been set up, seen and activated in the settings (com.ubuntu.calendar/calendar).

The synchronization can be started manually and seems to be doing something, but there are no appointments to be seen in the calendars. I was hoping that CALDAV would now work with this release candidate. Is there a log file that I can view and where can I find it?

If someone has a similar problem, I would be grateful for advice.