interceptor.js

//  Notify background of video information data necessary to render the video on another page.
//  The type of video (including codec) as well as the ArrayBuffer of video data.
var message = {
  buffer: this.response.slice(0),
  bufferType: videoInfo.type
};

//  Be sure to mark the buffer as transferable as it can be a large amount of data.
window.top.postMessage(message, origin, [message.buffer]);