title: How to add an extra button to the window title bar, so it will be work as standard?
body: <p>Firstly I want mention that I have already read all articles on SO on subject, but still have no answer for my question. Also my question slightly different than others.<br>
  Today a I have a look on Skype window. There is one extra button on it's title bar. But this button acts as native system button. Just look on glowing, <strong>it spreads out of the window</strong>. So I have the reasonable question. According to that we can see on the picture below, there is standard way to add extra button on title bar. But all answers on subj leads to hooking of <code>WM_NCPAINT</code> event and manual drawing of extra button. This approach is work but it could not yield such beautifull glowing as on the picture.<br>
  Does anybody knows the way to add standartized button on window's title bar? 
  Thanks in advance!<br>
  <img src="https://i.stack.imgur.com/kWh5e.png" alt="enter image description here"></p>