diff --git a/core/modules/language/language.routing.yml b/core/modules/language/language.routing.yml
index ba60f29..a3991df 100644
--- a/core/modules/language/language.routing.yml
+++ b/core/modules/language/language.routing.yml
@@ -34,9 +34,10 @@ language_delete:
     _entity_access: 'language_entity.delete'
 
 language_negotiation_browser:
-  pattern: 'admin/config/regional/language/detection/browser'
+  pattern: '/admin/config/regional/language/detection/browser'
   defaults:
     _form: '\Drupal\language\Form\NegotiationBrowserForm'
+    _title: 'Browser language detection configuration'
   requirements:
     _permission: 'administer languages'
 
diff --git a/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php b/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
index c4aab89..c7555c3 100644
--- a/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
+++ b/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
@@ -9,7 +9,7 @@
 
 use Drupal\Core\Config\ConfigFactory;
 use Drupal\Core\Config\Context\ContextInterface;
-use Drupal\Core\Extension\ModuleHandler;
+use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\system\SystemConfigFormBase;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -21,19 +21,18 @@ class NegotiationBrowserForm extends SystemConfigFormBase {
   /**
    * The module handler.
    *
-   * @var \Drupal\Core\Extension\ModuleHandler
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
    */
   protected $moduleHandler;
 
   /**
    * {@inheritdoc}
    *
-   * @param \Drupal\Core\Extension\ModuleHandler $module_handler
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler
    */
-  public function __construct(ConfigFactory $config_factory, ContextInterface $context, ModuleHandler $module_handler) {
-    $this->configFactory = $config_factory;
-    $this->configFactory->enterContext($context);
+  public function __construct(ConfigFactory $config_factory, ContextInterface $context, ModuleHandlerInterface $module_handler) {
+    parent::__construct($config_factory, $context);
     $this->moduleHandler = $module_handler;
   }
 
@@ -184,6 +183,12 @@ public function submitForm(array &$form, array &$form_state) {
     parent::submitForm($form, $form_state);
   }
 
+  /**
+   * Retrieves the browser's langcode mapping configuration array.
+   *
+   * @return array
+   *   The browser's langcode mapping configuration array.
+   */
   protected function language_get_browser_drupal_langcode_mappings() {
     $config = $this->configFactory->get('language.mappings');
     if ($config->isNew()) {