Examine source code of December Tree

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#2c542f",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "December Tree",
  "manifest_version": 2,
  "description": "<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/14fbef15c0b79b131028606567b2a7238f76ad7b2aab292fda6d38513b77ada9/http%3A//www.iammiti.blogspot.com\">http://www.iammiti.blogspot.com</a>"
}