Fatal error: Uncaught Error: Interface "Symfony\Component\Routing\Matcher\Dumper\MatcherDumperInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Routing/MatcherDumperInterface.php:11 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Routing/MatcherDumperInterface.php on line 11