The last upgrade of roundcubemail in the Kolab Debian11 repo from version 1:1.5.6.3-1~kolab1 to 1:1.5.6.4-1~kolab1 causes the login to fail.
Reverting back to the previous version (from cache) reverts the possibility to log in but breaks some functionalities.
When trying to log in the log shows the following message:
[21-Mar-2024 22:26:48 Europe/Berlin] PHP Fatal error: Uncaught Error: Cannot access private property kolab_ldap::$ready in /usr/share/roundcubemail/plugins/kolab_auth/kolab_auth.php:473 Stack trace: #0 /usr/share/roundcubemail/program/lib/Roundcube/rcube_plugin_api.php(516): kolab_auth->authenticate() #1 /usr/share/roundcubemail/index.php(114): rcube_plugin_api->exec_hook() #2 /usr/share/roundcubemail/public_html/index.php(26): include('/usr/share/roun...') #3 {main} thrown in /usr/share/roundcubemail/plugins/kolab_auth/kolab_auth.php on line 473