title: How to detect flash and prompt to install?
body: <p>If no flash is installed and one browses to <a href="http://www.plupload.com/example_custom.php" rel="nofollow noreferrer">http://www.plupload.com/example_custom.php</a> it'll launch a popup box:</p>
  
  <p><img src="https://i.stack.imgur.com/rMt7y.png" alt="enter image description here"></p>
  
  <p>How exactly are they doing this? Through some jQuery java-script code snippet or other?</p>
  
  <p>Second, I would like to know if there is a better way to inform the user that they need flash. Or is this an appropriate way?</p>