diff --git a/mozilla/xpfe/appshell/src/nsWebShellWindow.cpp b/mozilla/xpfe/appshell/src/nsWebShellWindow.cpp
index 20e9405efdf..3577385f09e 100644
--- a/mozilla/xpfe/appshell/src/nsWebShellWindow.cpp
+++ b/mozilla/xpfe/appshell/src/nsWebShellWindow.cpp
@@ -1248,6 +1248,7 @@ nsWebShellWindow::CreatePopup(nsIDOMElement* aElement, nsIDOMElement* aPopupCont
 
   // (9) Show the window. Don't give the focus yet because we may not want to.
   // For example, popup windows want focus, but tooltips do not.
+  window->SetSizeFromXUL();
   newWindow->Show(PR_TRUE);
 
   // (10) Do some layout.