[horde] CalDav calendar sync won't work after server change

[Frank Lienhard]

Hi List.

I have change the server of my shared hostig (uberspace.de)

I have 2 of those uberspace spaces.

One is my "testing" field, the other my productive system.
Ich changed both servers on the same way and have horde running on both.
After some hassle (see the centOS6 to 7 posts), I got it running. First
on my test space and then on my other system.

But I can only sync my calDav calendar on the testing system. I did the
identical adjustments on both, but still thunderbird says that my
calandars are "currently not available", even though the credentials not
the problem.

only difference is horde 5.2.12 (testig) and 5.2.16 productive. So at
the moment the older horde version works on PHP 7...

Only hint I have so far (phop error log, but unsire if that's the right
point to start):

[30-Nov-2020 20:52:41] WARNING: [pool www] child 19343 said into stderr:
"[30-Nov-2020 20:52:41 Europe/Berlin] PHP Deprecated:  Unparenthesized
`a ? b : c ? d : e` is deprecated. Use either `(a ? b : c) ? d : e` or
`a ? b : (c ? d : e)`  for ~horde/turba/lib/Driver.php on line 2660


[30-Nov-2020 21:10:06] WARNING: [pool www] child 21678 said into stderr:
"[30-Nov-2020 21:10:06 Europe/Berlin] PHP Fatal error:  Cannot use
result of built-in function in write context in
~pear/php/Archive/Tar.php on line 662

[30-Nov-2020 20:52:41] WARNING: [pool www] child 19343 said into stderr:
"[30-Nov-2020 20:52:41 Europe/Berlin] PHP Deprecated:  Array and string
offset access syntax with curly braces is deprecated in
~pear/php/Horde/Service/Weather.php on line 355"

any idea?