Minor change in the alert message.
diff --git a/js/ndnProtocol/content/ndnToolbar.js b/js/ndnProtocol/content/ndnToolbar.js
index 3716b98..078c7ad 100644
--- a/js/ndnProtocol/content/ndnToolbar.js
+++ b/js/ndnProtocol/content/ndnToolbar.js
@@ -2,7 +2,7 @@
 
 function ndnToolbarGetLatest(event){
   if (window._content.document.location.protocol != "ndn:") {
-    alert("The address must start with ndn");
+    alert("The address must start with ndn:");
     return;
   }