title: xvfb-run on OS X
body: <p>Is it possible to have xvfb-run on OS X?</p>
  
  <p>I develop a PHP application which uses xvfb-run. Before I worked on Ubuntu and it was OK. Now I've moved onto Mac and the application does not work.</p>
  
  <p>Or maybe any cross-platform alternative is available to use it on both Linux/OS X?</p>