diff -u b/core/lib/Drupal/Component/Utility/UrlHelper.php b/core/lib/Drupal/Component/Utility/UrlHelper.php
--- b/core/lib/Drupal/Component/Utility/UrlHelper.php
+++ b/core/lib/Drupal/Component/Utility/UrlHelper.php
@@ -4,7 +4,6 @@
 
 use Symfony\Component\Validator\Constraints\Url;
 use Symfony\Component\Validator\Constraints\NotBlank;
-use Symfony\Component\Validator\Constraints\NotBlankValidator;
 use Symfony\Component\Validator\Validation;
 
 /**