Examine source code of Crop Field

{
  "theme": {
    "images": {
      "theme_frame": "CropFieldHCustom.jpg"
    },
    "colors": {
      "frame": "#25bcc4",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Crop Field",
  "manifest_version": 2,
  "description": "sky, clouds, trees, field, crop, farm, country, wheat, oats, hay, My wallpaper to match can be found at: <a href=\"https://outgoing.prod.mozaws.net/v1/46d92516726ae26627ead7e9d1334f3b5ae6acbf16f303be8f792922a31f11c2/http%3A//nature.desktopnexus.com/wallpaper/744544/\" rel=\"nofollow\">http://nature.desktopnexus.com/wallpaper/744544/</a>"
}