diff --git a/src/config.js b/src/config.js
index 36fbdeb..9e8f588 100644
--- a/src/config.js
+++ b/src/config.js
@@ -3,7 +3,7 @@ var API_URL = 'https://api.form.io';
 
 // Parse query string
 var query = {};
-location.search.substr(1).split("&").forEach(function(item) {
+location.search.substring(1).split("&").forEach(function(item) {
   query[item.split("=")[0]] = item.split("=")[1] && decodeURIComponent(item.split("=")[1]);
 });