guardian/frontend — pull request #3514 by rich-nguyen (2014-03-13 17:08:45+00:00)
Title: Default script tag to async

It was very scary changing the script to defer. We don't know if the execution time of the js app has improved (render time looked fine, but DOMContentLoaded was delayed).

So I'm putting it behind a switch for now, and will add some means of measuring the performance.