title: ComboBox can't lose focus
body: <p>I have several comboboxes and all of them are manually entered text. After the combox selection couldn't lose focus. I used:</p>
  
  <pre><code>this.ActiveControl = null;
  </code></pre>
  
  <p>It works but the focus is going to the first control always.</p>
  
  <p>Could you please suggest to fix this issue?</p>