Examine source code of Castle 2

{
  "theme": {
    "images": {
      "theme_frame": "castle2.jpg"
    },
    "colors": {
      "frame": "#8f8b8b",
      "tab_background_text": "#0d0c0c"
    }
  },
  "version": "2.0",
  "name": "Castle 2",
  "manifest_version": 2
}