diff --git a/cms/templates/widgets/source-edit.html b/cms/templates/widgets/source-edit.html
index 6797fd224f..2475d03873 100644
--- a/cms/templates/widgets/source-edit.html
+++ b/cms/templates/widgets/source-edit.html
@@ -28,7 +28,7 @@
   </section>
 
   <script type = "text/javascript">
-require(["jquery", "codemirror/stex"], function($) {
+require(["jquery", "jquery.leanModal", "codemirror/stex"], function($) {
   hlstrig = $('#hls-trig-${hlskey}');
   hlsmodal = $('#hls-modal-${hlskey}');