diff --git a/mozilla/dom/src/base/nsGlobalWindow.cpp b/mozilla/dom/src/base/nsGlobalWindow.cpp
index 14130734f3a..4f3c2822593 100644
--- a/mozilla/dom/src/base/nsGlobalWindow.cpp
+++ b/mozilla/dom/src/base/nsGlobalWindow.cpp
@@ -604,7 +604,7 @@ GlobalWindowImpl::SetNewDocument(nsIDOMDocument* aDocument,
           ::JS_ClearRegExpStatics(cx);
 
           if (gsp) {
-            nsCOMPtr<nsIHTMLDocument> html_doc(do_QueryInterface(mDocument));
+            nsCOMPtr<nsIHTMLDocument> html_doc(do_QueryInterface(aDocument));
 
             nsWindowSH::InstallGlobalScopePolluter(cx, mJSObject, gsp,
                                                    html_doc);