Can't record video

Hi,

I'm trying to use this library without success. I've ported the example from 'threejs_webgl_postprocessing.html' to this jsfidle:

https://jsfiddle.net/onwbudmr/

The 3D scene is fine, but none of the methods I'm using are working:

  - Using 'THREEcapUI' doesn't trigger any save.
  - Calling 'capture.record' is not resolving or rejecting.

Any help would be appreciated.