title: Dynamic selectees not working in JQuery-UI selectable
body: <p>I am crating a windows like interface where I have a canvas and into it I can append multiple icons dynamically. I have set the canvas to selectable.
  The problem is that when I add new icons, I can't select them.</p>
  
  <p>I tried adding ui-selectee class to the icon but it doesn't work either.</p>
  
  <pre><code>$('.canvas').selectable({ 
     filter: $('.icons'),
     autoRefresh: true,  
  });
  </code></pre>