Multiple document editing - timestamp & activity NOT updated

Nextcloud version (19.0.1):
Operating system and version (Ubuntu 18.04):
Apache or nginx version (Apache 2.4.29):
PHP version (7.2.24):

The issue you are facing:
When multiple user edit a document via ONLYOFFICE, the ‘Activity’ tab & the timestamp ‘last changed’ in the nextcloud files view is NOT updated. The changes itself are present in the document and are beeing synced to desktop client as well.
Even when all editing users exit the document, there’s no update to the metadata of the document.

Is this the first time you’ve seen this error? (Y/N): YES

Steps to replicate it:

  1. create word-document
  2. have 2 (or more) users edit the document via ONLYOFFICE
  3. check the ‘last changed’ and ‘Activity’ info
  4. have every editing user exit the document
  5. check the ‘last changed’ and ‘Activity’ info

The output of your Nextcloud log in Admin > Logging:

no entries in logfile other than the REQUESTS

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'instanceid' => 'REMOVED',
  'passwordsalt' => 'REMOVED',
  'secret' => 'REMOVED',
  'trusted_domains' =>
  array (
    0 => 'REMOVED',
  'datadirectory' => '/var/nextcloud/data',
  'overwrite.cli.url' => 'REMOVED',
  'dbtype' => 'pgsql',
  'version' => '',
  'dbname' => 'xcloud',
  'dbhost' => 'localhost:5432',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'oc_admin',
  'dbpassword' => 'REMOVED',
  'installed' => true,
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'mail_smtpmode' => 'sendmail',
  'mail_smtpauthtype' => 'LOGIN',
  'maintenance' => false,
  'theme' => '',
  'log_type' => 'file',
  'logfile' => '/var/log/nextcloud.log',
  'logfilemode' => 416,
  'logdateformat' => 'F d, Y H:i:s',
  'loglevel' => 2,
  'mail_from_address' => 'cloud',
  'mail_domain' => 'REMOVED',
  '' => 'stable',
  'mail_sendmailmode' => 'smtp',
  'mail_smtpauth' => 1,
 'allow_local_remote_servers' => true,

The output of your Apache/nginx/system log in /var/log/____: