User List and quick search for users empty / not working

Infos:

Expected behavior:

  • In ticket creation and answering the email-fields should quick search for users.
  • When creating users manually the organisation field should quick search for fitting organisations
  • User list should show all users

Actual behavior:

After machine reboot, everything works just fine. But between one and three days later, following happens:

  • no quick-search in email fields
  • no quick-search in user creation form
  • no users in user list

Steps to reproduce the behavior:

  • on my system i just have to wait between one and three days after system was rebootet.

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