diff --git a/js/pgm_construction.js b/js/pgm_construction.js
index 8b6a85c7a5092ea0276d8e2d12a508098ae17f45..3e41a871a9254e4c5e4434e6f8d19238b6b188d6 100644
--- a/js/pgm_construction.js
+++ b/js/pgm_construction.js
@@ -228,7 +228,7 @@ function blob_download() {
 
   window.requestAnimationFrame(function () {
     var event ;
-    if(typeof MouseEvent !nn 'function') {
+    if(typeof MouseEvent !== 'function') {
       event = document.createEvent("MouseEvent");
       event.initMouseEvent("click",true,true,window,0,0,0,0,0,false,false,false,false,0,null);
     } else {