Plesk can not be updated or is not accessible: Class Laminas\ServiceManager\ServiceLocatorInterface cannot implement previously implemented interface
Symptoms
Plesk update fails or Plesk panel cannot be accessed with the following message:
PHP Fatal error: Class Laminas\ServiceManager\ServiceLocatorInterface cannot implement previously implemented interface Psr\Container\ContainerInterface in /opt/psa/admin/plib/modules/monitoring/vendor/laminas/laminas-servicemanager/src/ServiceLocatorInterface.php on line 18
Cause
The outdated version of the Monitoring extension is installed on the server.