Examine source code of Mouse Island

{
  "theme": {
    "images": {
      "theme_frame": "MouseIslandH.jpg"
    },
    "colors": {
      "frame": "#fbf9ff",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Mouse Island",
  "manifest_version": 2,
  "description": "fantasy, mice, mouse, mushroom, house, toadstool, island, bridge, water, grass, My wallpaper to match can be found at: <a href=\"https://outgoing.prod.mozaws.net/v1/4c07eba24537469c7908d73bb820901961553097fd20eef657370bc5134f587b/http%3A//animals.desktopnexus.com/wallpaper/777607/\" rel=\"nofollow\">http://animals.desktopnexus.com/wallpaper/777607/</a>"
}