diff --git a/core/modules/system/lib/Drupal/system/Tests/Menu/BreadcrumbTest.php b/core/modules/system/lib/Drupal/system/Tests/Menu/BreadcrumbTest.php
index 646ccc6..88d6e8c 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Menu/BreadcrumbTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Menu/BreadcrumbTest.php
@@ -7,6 +7,8 @@
 
 namespace Drupal\system\Tests\Menu;
 
+use Drupal\Component\Utility\Unicode;
+
 /**
  * Menu breadcrumbs related tests.
  */