diff --git a/js/index.php b/js/index.php
index f41fc7cc4a3..b84408c6804 100644
--- a/js/index.php
+++ b/js/index.php
@@ -72,6 +72,7 @@
 	'../external/jquery-ui/widgets/checkboxradio.js',
 	'../external/jquery-ui/widgets/button.js',
 	'widgets/forms/button.js',
+	'widgets/forms/button.backcompat.js',
 	'widgets/navbar.js',
 	'widgets/navbar.backcompat.js',
 	'widgets/popup.js',