diff --git a/koha-tmpl/intranet-tmpl/prog/en/modules/patron_lists/patron-lists-tab.tt b/koha-tmpl/intranet-tmpl/prog/en/modules/patron_lists/patron-lists-tab.tt
index 7ec72d337f..4e124ca209 100644
--- a/koha-tmpl/intranet-tmpl/prog/en/modules/patron_lists/patron-lists-tab.tt
+++ b/koha-tmpl/intranet-tmpl/prog/en/modules/patron_lists/patron-lists-tab.tt
@@ -123,8 +123,8 @@
     <p>Patron is not on any list. <a href="/cgi-bin/koha/patron_lists/add-modify.pl">Create a new patron list</a>.</p>
 [% END %]
 <script>
-    const patron_id = "[% borrowernumber | html %]";
-    const cardnumber = "[% cardnumber | html %]";
+    var patron_id = "[% borrowernumber | html %]";
+    var cardnumber = "[% cardnumber | html %]";
     addPermissions({
         CAN_user_tools_manage_patron_lists: [% CAN_user_tools_manage_patron_lists ? 1 : 0 | html %],
     });