diff -u b/core/includes/common.inc b/core/includes/common.inc
--- b/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -286,7 +286,7 @@
  *   TRUE if the address is in a valid format.
  */
 function valid_email_address($mail) {
-  return \Drupal::service('email.validator')->isValid($mail);
+  return \Drupal::emailValidator()->isValid($mail);
 }
 
 /**
only in patch2:
unchanged:
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -647,4 +647,14 @@ public static function accessManager() {
     return static::$container->get('access_manager');
   }
 
+  /**
+   * Returns the email validator service.
+   *
+   * @return \Egulias\EmailValidator\EmailValidator
+   *   The email validator service.
+   */
+  public static function emailValidator() {
+    return static::$container->get('email.validator');
+  }
+
 }