Update split.js

split.js

@@ -82,7 +82,7 @@ function dragend() {
   dragging = false;
 }
 
-if (window.addEventListener) {
+if (window.addEventListener && document.getElementById("container") != null) {
   console.log(document.getElementById("dragbar"));
   console.log("****************")
   document.getElementById("dragbar").addEventListener("mousedown", function(e) {dragstart(e);});