title: Base64URL decoding via JavaScript?
body: <p>So I'm stumped. I know there's lots of Base64 encoders/decoders for JS, but not for the modified (and Facebook-favored) Base64URL variation. So far searching across stackoverflow has come up dry.</p>
  
  <p>Yes, I could use PHP or another server-side library to decode this, but I'm trying to keep this universal regardless of what platform I'm using... for example, if I were to host a HTML-only Facebook app on Amazon S3/CloudFront and only use their JS SDK and jQuery to take care of processing forms and getting data.</p>
  
  <p>That said, does anyone know of any Base64URL-specific decoders for JavaScript?</p>
  
  <p>Thanks in advance!</p>