--- a/xpfe/appshell/src/nsWebShellWindow.cpp
+++ b/xpfe/appshell/src/nsWebShellWindow.cpp
@@ -87,22 +87,16 @@ nsWebShellWindow::nsWebShellWindow(PRUin
   : nsXULWindow(aChromeFlags)
   , mSPTimerLock("nsWebShellWindow.mSPTimerLock")
 {
 }
 
 
 nsWebShellWindow::~nsWebShellWindow()
 {
-  if (mWindow) {
-    mWindow->SetClientData(0);
-    mWindow->Destroy();
-    mWindow = nullptr; // Force release here.
-  }
-
   MutexAutoLock lock(mSPTimerLock);
   if (mSPTimer)
     mSPTimer->Cancel();
 }
 
 NS_IMPL_ADDREF_INHERITED(nsWebShellWindow, nsXULWindow)
 NS_IMPL_RELEASE_INHERITED(nsWebShellWindow, nsXULWindow)