diff --git a/core/modules/config/lib/Drupal/config/Controller/ConfigController.php b/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
index 68896d5..632dd0c 100644
--- a/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
+++ b/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
@@ -94,7 +94,7 @@ public function diff($config_file) {
 
     // @todo Remove use of drupal_set_title() when
     //   http://drupal.org/node/1871596 is in.
-    drupal_set_title('View changes of @config_file', array('@config_file' => $config_file));
+    drupal_set_title(format_string('View changes of @config_file', array('@config_file' => $config_file)));
 
     return $output;
   }