diff --git a/core/modules/system/tests/modules/form_test/form_test.module b/core/modules/system/tests/modules/form_test/form_test.module
index 03b7cb8..8feed17 100644
--- a/core/modules/system/tests/modules/form_test/form_test.module
+++ b/core/modules/system/tests/modules/form_test/form_test.module
@@ -2097,6 +2097,7 @@ function form_test_clicked_button($form, &$form_state) {
       // Image buttons need a #src; the others need a #value.
       if ($type == 'image_button') {
         $form[$name]['#src'] = 'core/misc/druplicon.png';
+        $form[$name]['#value'] = $name;
       }
       else {
         $form[$name]['#value'] = $name;