Examine source code of Brighter World

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Brighter World",
  "manifest_version": 2,
  "description": "Black theme with an image of the earth at night by <a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/e2064536f750d68fb7a4fd51162f179e0cdbeaea0512487f17270249e4dbbbd3/http%3A//istockphoto.com\">istockphoto.com</a>"
}