title: Compatibility of window.crypto.getRandomValues()
body: <p>I need to generate cryptographically secure pseudorandom numbers, in Javascript.  I know about the <code>window.crypto.getRandomValues</code> API, which does exactly what I want.  However, I also know it was introduced relatively recently (in 2011 or so).</p>
  
  <p>Can I safely assume <code>window.crypto.getRandomValues</code> is present, or will using it introduce compatibility problems on some browsers?  Are there any major (widely used) browsers which do not support <code>window.crypto.getRandomValues</code> (including mobile or desktop browsers), and if so, which ones do I need to worry about?  I would be delighted to learn that there is enough support that I no longer need to worry about <a href="https://security.stackexchange.com/q/20029/971">fallback methods</a>, if that is indeed the case.</p>