Examine source code of Tranquil Landscape

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#444734",
      "tab_background_text": "#fbfff5"
    }
  },
  "version": "2.0",
  "name": "Tranquil Landscape",
  "manifest_version": 2,
  "description": "Stock credit: <a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/e20eb6aa5e5b5d4b21e1f5f12256ed8e578ca602d79c5c9df900d81bfc5deecd/https%3A//pixabay.com/en/users/jpeter2-697843/\">Jörg Peter \n</a>"
}