diff --git a/wagtail/wagtailadmin/static/wagtailadmin/js/page-editor.js b/wagtail/wagtailadmin/static/wagtailadmin/js/page-editor.js
index 96eed6bf6..06dba9b90 100644
--- a/wagtail/wagtailadmin/static/wagtailadmin/js/page-editor.js
+++ b/wagtail/wagtailadmin/static/wagtailadmin/js/page-editor.js
@@ -346,7 +346,7 @@ $(function() {
         function submitPreview(enhanced){
             $.ajax({
                 type: "POST",
-                url: $(this).data('action'),
+                url: $this.data('action'),
                 data: $('#page-edit-form').serialize(),
                 success: function(data, textStatus, request) {
                     if (request.getResponseHeader('X-Wagtail-Preview') == 'ok') {