Examine source code of CSSJockey

{
  "theme": {
    "images": {
      "theme_frame": "firefox-personas-heading.png"
    },
    "colors": {
      "frame": "#c9c9c9",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "CSSJockey",
  "manifest_version": 2,
  "description": "<a href=\"https://outgoing.prod.mozaws.net/v1/598ab65de2ce4998e861e0704f0a4799eaefeb0b6d271c514b6a4b97bc7b9dfb/http%3A//CSSJockey.com\" rel=\"nofollow\">CSSJockey.com</a>"
}