title: Subscribing to UI Automation event freezes application on window hang
body: <p>I'm using AddPropertyChangedEventHandler to subscribe to a window event as per <a href="http://msdn.microsoft.com/en-us/library/ms752286(v=vs.110).aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/ms752286(v=vs.110).aspx</a></p>
  
  <p>However, if the target window hangs or freezes (unfortunately this can happen fairly regularly), my entire application hangs as well.</p>
  
  <p>What is the best way to overcome this problem?</p>
  
  <p>(C#, .NET 4.5, WPF)</p>