Examine source code of Dark Stormy Night

{
  "theme": {
    "images": {
      "theme_frame": "HorsesNightmareHCustom.jpg"
    },
    "colors": {
      "frame": "#1d0342",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Dark Stormy Night",
  "manifest_version": 2,
  "description": "horse, sky, lightning, sky, clouds, grass, storm, rain, fright, farm, ranch, light, bright, dark, My wallpaper to match can be found at: <a href=\"https://outgoing.prod.mozaws.net/v1/849f45f529fbb6c3ac9c247fb26708999e2ae5149fd989b7f03d137980d0ceb0/http%3A//nature.desktopnexus.com/wallpaper/700339/\" rel=\"nofollow\">http://nature.desktopnexus.com/wallpaper/700339/</a>"
}