diff --git a/lib/hashauth.js b/lib/hashauth.js
index 1421c076535..8848ca08ef0 100644
--- a/lib/hashauth.js
+++ b/lib/hashauth.js
@@ -91,7 +91,12 @@ hashauth.init = function init(client, $) {
   hashauth.requestAuthentication = function requestAuthentication (eventOrNext) {
     var translate = client.translate;
     hashauth.injectHtml();
-    var clientWidth = Math.min(400, $( '#container')[0].clientWidth);
+
+    var clientWidth = window.innerWidth
+      || document.documentElement.clientWidth
+      || document.body.clientWidth;
+
+    clientWidth = Math.min(400, clientWidth);
 
     $( '#requestauthenticationdialog' ).dialog({
         width: clientWidth