title: WPF Dialog not modal?
body: <p>I have a Window which I show by dispatching the ShowDialog() call on the ui thread (I am on another thread):</p>
  
  <pre><code>myMainWindowDispatcher.BeginInvoke(new Func&lt;bool?&gt;(myDialog.ShowDialog));
  </code></pre>
  
  <p>myDialog's Owner has been set to myMainWindow. When the dialog shows it is correctly always on top however I am able to interact with the Window behind! (defeating the purpose of making it modal which is required). I used to do the same thing, i.e. dispatch the call from another thread and it used to work, i.e. was modal. Now for the life of me I cannot figure out why it is not. I cannot paste my whole project code here - can you think of anything that would make the Window non modal??</p>