init

config/routes/framework.php

@@ -0,0 +1,11 @@
+<?php declare(strict_types=1);
+
+use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;
+
+return static function (RoutingConfigurator $routingConfigurator): void {
+    if ($routingConfigurator->env() === 'dev') {
+        $routingConfigurator
+            ->import('@FrameworkBundle/Resources/config/routing/errors.xml')
+            ->prefix('/_error');
+    }
+};