title: Forecolor from parent doesn't work with groupbox text and combobox
body: <p>I am currently trying to change the forecolor of my Winforms vb.net application.
  So I change the forecolor of my main Form and all the controls inside must get the new value if the forecolor has not been set otherwise (by ambient property functionality).</p>
  <p>It doesn't work with must of the controls but not with :</p>
  <ul>
  <li>Groupbox (groupbox text doesn't change but children does)</li>
  <li>Combobox</li>
  </ul>
  <p>I have tried in another application and it is the same.</p>
  <p>Here is the result:</p>
  <ul>
  <li>Before color change: <a href="https://i.stack.imgur.com/IhgE8.png" rel="nofollow noreferrer">1</a></li>
  <li>After color change: <a href="https://i.stack.imgur.com/I9Kyu.png" rel="nofollow noreferrer">2</a></li>
  </ul>
  <p>Why? How to fix this?</p>
  <p>Thanks</p>