title: How to cancel opening popup with beforeClose callback ? #magnific-popup
body: <p>I'm using a MagnificPopup with a beforeClose callback and I'd like to cancel its opening depending on a condition. How can I do that ?</p>
  
  <p>I tried a return <code>false</code>, or a <code>$.magnificPopup.close();</code> but it still opens...</p>
  
  <p>I'm sure there is a basic solution !</p>
  
  <p>Thanks</p>