Examine source code of Popcorn2

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Popcorn2",
  "manifest_version": 2,
  "description": "<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/54956d9d15128ee6cfe0fd455c1590ca89aa1f317333bbdc661b0f14c7c663f3/http%3A//www.youtube.com/watch%3Fv=DBYjZTdrJlA\">http://www.youtube.com/watch?v=DBYjZTdrJlA</a>\n\n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/d9f74054ccce7531e97f8c3d92d0600070d8d08102876fd2ab54eb262e614b9c/https%3A//www.youtube.com/watch%3Fv=XaKx3kUjsLk\">https://www.youtube.com/watch?v=XaKx3kUjsLk</a>"
}