Issue #2469929 by mondrake, Bojan Živkov, LewisNyman, tim.plunkett, Bojhan, roderik: The confirmation forms' cancel link should be styled as a button

core/lib/Drupal/Core/Form/ConfirmFormHelper.php

@@ -44,6 +44,7 @@ class ConfirmFormHelper {
     return [
       '#type' => 'link',
       '#title' => $form->getCancelText(),
+      '#attributes' => ['class' => ['button']],
       '#url' => $url,
     ];
   }