Examine source code of Beutiful Landscape

{
  "theme": {
    "images": {
      "theme_frame": "xbox-360-wallpaper-4_phixr2.jpg"
    },
    "colors": {
      "frame": "#039aff",
      "tab_background_text": "#19ba00"
    }
  },
  "version": "2.0",
  "name": "Beutiful Landscape",
  "manifest_version": 2,
  "description": "Nice and pretty to go on your Firefox!"
}