PHP Upgrade to 8.3 -> Login fails

[chmali]

Hello everyone,
I have a Roundcube installation (1.6.6) running on my system. It runs via a php socket. Currently I have PHP 8.2 and 8.3 running in parallel. I can move the configuration files from pool.d under php/8.2/fpm/pool.d to php/8.3/fpm/pool.d, restart both php-fpm versions and then the applications run on the new PHP version. That worked so far for all applications except Roundcube. The login dialog appears, but after login I get the message:


Oops... something went wrong!
An internal error has occurred. Your request cannot be processed at this time.
For administrators: Please check the application and/or server error logs for more information.

I can't find anything related to this issue in the log files.
Have any of you experienced this and solved it?

Thanks for your answers!
chmali

[SKaero]

Check the Roundcube error log at <RC root>/logs/errors

[chmali]

Sorry for answering not earlier. errors.log is empty.