Examine source code of Fenced Tree

{
  "theme": {
    "images": {
      "theme_frame": "forefoxpersonaboxedtree.jpg"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#666666"
    }
  },
  "version": "2.0",
  "name": "Fenced Tree",
  "manifest_version": 2,
  "description": "A snow scene of a tree with a protective fence around it and a fallen log."
}