title: Close any browser tab from an HTML button
body: <p>I have an HTML button and I need to close the tab by clicking on it.</p>
  
  <p>It must work on Chrome and Firefox and seems the common methods are not detecting from the new browser versions.</p>
  
  <p>I just tried these two and not worked. </p>
  
  <p><code>&lt;a href="#" onclick="javascript:window.close();opener.window.focus();"&gt;C‌​lose&lt;/a&gt;</code></p>
  
  <p>AND </p>
  
  <p><code>&lt;button onclick="self.close()"&gt;Close&lt;/button&gt;</code> Both did not work. </p>
  
  <p>Please, can you help me?</p>