Examine source code of Fox Field

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#855b3f",
      "tab_background_text": "#ffebd9"
    }
  },
  "version": "2.0",
  "name": "Fox Field",
  "manifest_version": 2,
  "description": "Stock credit: David Mark \n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/1f4e9cabb8c69a1b5bcec47ef4d6f3317a3882677483cdcd54f67508accb2971/https%3A//pixabay.com/\">https://pixabay.com/</a>"
}