diff --git a/core/lib/Drupal/Core/Form/ConfirmFormHelper.php b/core/lib/Drupal/Core/Form/ConfirmFormHelper.php
index 61d77dd..0902613 100644
--- a/core/lib/Drupal/Core/Form/ConfirmFormHelper.php
+++ b/core/lib/Drupal/Core/Form/ConfirmFormHelper.php
@@ -44,6 +44,7 @@ public static function buildCancelLink(ConfirmFormInterface $form, Request $requ
     return [
       '#type' => 'link',
       '#title' => $form->getCancelText(),
+      '#attributes' => ['class' => ['button']],
       '#url' => $url,
     ];
   }