diff --git a/grade/report/singleview/classes/local/screen/tablelike.php b/grade/report/singleview/classes/local/screen/tablelike.php
index 6d06f36acf0..38b2d95eabc 100644
--- a/grade/report/singleview/classes/local/screen/tablelike.php
+++ b/grade/report/singleview/classes/local/screen/tablelike.php
@@ -225,7 +225,7 @@ abstract class tablelike extends screen implements be_readonly {
         return html_writer::tag(
             'div',
             (new bulk_insert($this->item))->html(),
-            ['class' => 'singleview_bulk', 'hidden' => true]
+            ['class' => 'singleview_bulk', 'hidden' => 'hidden']
         );
     }