diff --git a/browser/base/content/browser.js b/browser/base/content/browser.js
index 429e71a7e0ed..dd242cb8aba0 100644
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -618,8 +618,8 @@ function BrowserStartup()
 #endif
 
   var sidebarSplitter;
-  if (window.opener && !window.opener.closed && window.opener.gFindBar) {
-    if (window.opener.gFindBar.mFindMode == FIND_NORMAL) {
+  if (window.opener && !window.opener.closed) {
+    if (window.opener.gFindBar && window.opener.gFindBar.mFindMode == FIND_NORMAL) {
       var openerFindBar = window.opener.document.getElementById("FindToolbar");
       if (openerFindBar && !openerFindBar.hidden)
         gFindBar.openFindBar();