title: A WPF window doesn't release the memory after closed
body: <p>I created a test code:</p>
  <pre><code>private void Application_Startup_1(object sender, StartupEventArgs e)
  {
      ShutdownMode = System.Windows.ShutdownMode.OnExplicitShutdown;
      MainWindow window = new MainWindow();
      window.Show();
      window.Close();
      window = null;
      GC.Collect();
  }
  </code></pre>
  <p>The MainWindow is a automatic created window by Visual Studio and I haven't add any code to it.
  Before the line &quot;MainWindow window = new MainWindow();&quot;, the application occupies 4M memory. When the window is opened, it became 13M. <strong>It doesn't change even if we close the window and call the GC.Collect()</strong></p>
  <p>What are these extra memory being used for and how can we release them?</p>