Examine source code of Our Blue Planet

{
  "theme": {
    "images": {
      "theme_frame": "Earth-and-Moon.jpg"
    },
    "colors": {
      "frame": "#000088",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Our Blue Planet",
  "manifest_version": 2,
  "description": "Earth and Moon against a dark starry background."
}