title: Typo3 update 9.5.16 Page tree error for non admin users
body: <p>After the update from typo3 9.5.15 to 9.5.16, a backend-user does not see the page tree, instead, there is a message:</p>
  
  <p>"Page tree error" "Got unexpected response from the server. Please check logs for details." /
  Seitenbaumfehler  "Unerwartete Antwort vom Server erhalten. Bitte überprüfen Sie die Protokolle für mehr Details."</p>
  
  <p>I updated a copy of the system to 10.4.1 - the same problem.</p>
  
  <p>Admins are not affected.</p>
  
  <p>No error is shown in the log-file.</p>
  
  <p>I changed the debug settings to Debug[Active] and no errors are shown.</p>
  
  <p>When I go back to 9.5.15 the problem disappears.</p>
  
  <p><strong>This problem was fixed with the update to 9.5.17 or 10.4.2!</strong></p>