Fatal error: Uncaught Error: Class "Piwik\Updater\UpdateObserver" not found in /usr/home/mw2p5ujyzt/www/htdocs/mode2_piwik/plugins/CoreUpdater/Commands/Update/CliUpdateObserver.php:21 Stack trace: #0 {main} thrown in /usr/home/mw2p5ujyzt/www/htdocs/mode2_piwik/plugins/CoreUpdater/Commands/Update/CliUpdateObserver.php on line 21