Use language setting of users when logging in.

config/packages/security.yaml

@@ -28,6 +28,7 @@ security:
                 check_path: login
                 csrf_token_generator: security.csrf.token_manager
                 use_referer: true
+                default_target_path: '/'
 
             logout:
                 path: logout

config/routes.yaml

@@ -1,3 +1,10 @@
 #index:
 #    path: /
 #    controller: App\Controller\DefaultController::index
+
+# Redirect every url without an locale to the locale of the user/the global base locale
+redirector:
+    path: /{url}
+    requirements:
+        url: ".*"
+    controller: App\Controller\RedirectController:addLocalePart

config/routes/annotations.yaml

@@ -2,7 +2,4 @@ controllers:
     resource: ../../src/Controller/
     type: annotation
 
-    prefix:
-        en: '/en'
-        de: '/de'
-        '%locale%': '/'
+    prefix: '{_locale}'

config/services.yaml

@@ -49,6 +49,10 @@ services:
             - name: doctrine.orm.entity_listener
 
 
+    App\Controller\RedirectController:
+        arguments:
+            $default_locale: '%locale%'
+
     App\Command\UpdateExchangeRatesCommand:
         arguments:
             $base_current: '%default_currency%'