Nextcloud login problem after upgrade from 20.0.2 to 20.0.8

I did Nextcloud upgrade from 20.0.2 to 20.0.8 on a Univention UCS Server (Nextcloud installed on docker) and now users can’t login. We can insert login credentials but after we receive an Internal Server Error page with ID request for server administrator.

Looking in /var/lib/univention-appcenter/apps/nextcloud/data/nextcloud-data/nextcloud.log I found this related to the login ID request error code. Is this a bug on nextcloud update? How can I login agin correctly?

{"reqId":"WsoCPuJYTD3kWvkKPemL","level":0,"time":"2021-03-24T08:31:46+00:00","remoteAddr":"192.168.0.177","user":"Administrator","app":"files_sharing","method":"GET","url":"/nextcloud/apps/dashboard/","message":"/appinfo/app.php is deprecated, use \\OCP\\AppFramework\\Bootstrap\\IBootstrap on the application class instead.","userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Safari/605.1.15","version":"20.0.8.1"}
{"reqId":"WsoCPuJYTD3kWvkKPemL","level":0,"time":"2021-03-24T08:31:46+00:00","remoteAddr":"192.168.0.177","user":"Administrator","app":"onlyoffice","method":"GET","url":"/nextcloud/apps/dashboard/","message":"/appinfo/app.php is deprecated, use \\OCP\\AppFramework\\Bootstrap\\IBootstrap on the application class instead.","userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Safari/605.1.15","version":"20.0.8.1"}
{"reqId":"WsoCPuJYTD3kWvkKPemL","level":3,"time":"2021-03-24T08:31:46+00:00","remoteAddr":"192.168.0.177","user":"Administrator","app":"index","method":"GET","url":"/nextcloud/apps/dashboard/","message":{"Exception":"Doctrine\\DBAL\\Exception\\TableNotFoundException","Message":"An exception occurred while executing 'SELECT \"r\".*, \"p\".* FROM \"oc_talk_rooms\" \"r\" LEFT JOIN \"oc_talk_participants\" \"p\" ON (\"p\".\"user_id\" = ?) AND (\"p\".\"room_id\" = \"r\".\"id\") WHERE \"p\".\"user_id\" IS NOT NULL' with params [\"Administrator\"]:\n\nSQLSTATE[42P01]: Undefined table: 7 ERRORE:  la relazione \"oc_talk_participants\" non esiste\nLINE 1: ...T \"r\".*, \"p\".* FROM \"oc_talk_rooms\" \"r\" LEFT JOIN \"oc_talk_p...\n                                                             ^","Code":0,"Trace":[{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/DBALException.php","line":169,"function":"convertException","class":"Doctrine\\DBAL\\Driver\\AbstractPostgreSQLDriver","type":"->"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/DBALException.php","line":149,"function":"wrapException","class":"Doctrine\\DBAL\\DBALException","type":"::"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php","line":914,"function":"driverExceptionDuringQuery","class":"Doctrine\\DBAL\\DBALException","type":"::"},{"file":"/var/www/html/lib/private/DB/Connection.php","line":202,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Query/QueryBuilder.php","line":206,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/html/lib/private/DB/QueryBuilder/QueryBuilder.php","line":217,"function":"execute","class":"Doctrine\\DBAL\\Query\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Manager.php","line":294,"function":"execute","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Share/RoomShareProvider.php","line":779,"function":"getRoomsForParticipant","class":"OCA\\Talk\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Share20/Manager.php","line":1332,"function":"getSharedWith","class":"OCA\\Talk\\Share\\RoomShareProvider","type":"->"},{"file":"/var/www/html/apps/files_sharing/lib/MountProvider.php","line":80,"function":"getSharedWith","class":"OC\\Share20\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Files/Config/MountProviderCollection.php","line":119,"function":"getMountsForUser","class":"OCA\\Files_Sharing\\MountProvider","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":452,"function":"addMountForUser","class":"OC\\Files\\Config\\MountProviderCollection","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":377,"function":"initMountPoints","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/private/legacy/OC_Util.php","line":322,"function":"init","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/base.php","line":1007,"function":"setupFS","class":"OC_Util","type":"::"},{"file":"/var/www/html/index.php","line":37,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Driver/AbstractPostgreSQLDriver.php","Line":63,"Previous":{"Exception":"Doctrine\\DBAL\\Driver\\PDOException","Message":"SQLSTATE[42P01]: Undefined table: 7 ERRORE:  la relazione \"oc_talk_participants\" non esiste\nLINE 1: ...T \"r\".*, \"p\".* FROM \"oc_talk_rooms\" \"r\" LEFT JOIN \"oc_talk_p...\n                                                             ^","Code":"42P01","Trace":[{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php","line":906,"function":"execute","class":"Doctrine\\DBAL\\Driver\\PDOStatement","type":"->"},{"file":"/var/www/html/lib/private/DB/Connection.php","line":202,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Query/QueryBuilder.php","line":206,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/html/lib/private/DB/QueryBuilder/QueryBuilder.php","line":217,"function":"execute","class":"Doctrine\\DBAL\\Query\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Manager.php","line":294,"function":"execute","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Share/RoomShareProvider.php","line":779,"function":"getRoomsForParticipant","class":"OCA\\Talk\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Share20/Manager.php","line":1332,"function":"getSharedWith","class":"OCA\\Talk\\Share\\RoomShareProvider","type":"->"},{"file":"/var/www/html/apps/files_sharing/lib/MountProvider.php","line":80,"function":"getSharedWith","class":"OC\\Share20\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Files/Config/MountProviderCollection.php","line":119,"function":"getMountsForUser","class":"OCA\\Files_Sharing\\MountProvider","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":452,"function":"addMountForUser","class":"OC\\Files\\Config\\MountProviderCollection","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":377,"function":"initMountPoints","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/private/legacy/OC_Util.php","line":322,"function":"init","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/base.php","line":1007,"function":"setupFS","class":"OC_Util","type":"::"},{"file":"/var/www/html/index.php","line":37,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php","Line":129,"Previous":{"Exception":"PDOException","Message":"SQLSTATE[42P01]: Undefined table: 7 ERRORE:  la relazione \"oc_talk_participants\" non esiste\nLINE 1: ...T \"r\".*, \"p\".* FROM \"oc_talk_rooms\" \"r\" LEFT JOIN \"oc_talk_p...\n                                                             ^","Code":"42P01","Trace":[{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php","line":127,"function":"execute","class":"PDOStatement","type":"->"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php","line":906,"function":"execute","class":"Doctrine\\DBAL\\Driver\\PDOStatement","type":"->"},{"file":"/var/www/html/lib/private/DB/Connection.php","line":202,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Query/QueryBuilder.php","line":206,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/html/lib/private/DB/QueryBuilder/QueryBuilder.php","line":217,"function":"execute","class":"Doctrine\\DBAL\\Query\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Manager.php","line":294,"function":"execute","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/html/apps/spreed/lib/Share/RoomShareProvider.php","line":779,"function":"getRoomsForParticipant","class":"OCA\\Talk\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Share20/Manager.php","line":1332,"function":"getSharedWith","class":"OCA\\Talk\\Share\\RoomShareProvider","type":"->"},{"file":"/var/www/html/apps/files_sharing/lib/MountProvider.php","line":80,"function":"getSharedWith","class":"OC\\Share20\\Manager","type":"->"},{"file":"/var/www/html/lib/private/Files/Config/MountProviderCollection.php","line":119,"function":"getMountsForUser","class":"OCA\\Files_Sharing\\MountProvider","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":452,"function":"addMountForUser","class":"OC\\Files\\Config\\MountProviderCollection","type":"->"},{"file":"/var/www/html/lib/private/Files/Filesystem.php","line":377,"function":"initMountPoints","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/private/legacy/OC_Util.php","line":322,"function":"init","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/html/lib/base.php","line":1007,"function":"setupFS","class":"OC_Util","type":"::"},{"file":"/var/www/html/index.php","line":37,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/html/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php","Line":127}},"CustomMessage":"--"},"userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Safari/605.1.15","version":"20.0.8.1"}

I upgraded in the same context (univention) and discovered had to disable the talk app.
Maybe it helps - until a fix is available.

do a:
univention-app shell nextcloud sudo -u www-data /var/www/html/occ app:disable spreed

it may help
I discovered some table doesn’t exist in log files:
undefined table: 7 FEHLER: Relation »oc_talk_participants« existiert nicht

This problem also remains in the upgrade from 20.0.2 to 20.0.9. The temporary solution of disable Talk app works.