Examine source code of The Old Park

{
  "theme": {
    "images": {
      "theme_frame": "FirefoxPersonaTheOldParkH.jpg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "The Old Park",
  "manifest_version": 2,
  "description": "The edge of an ancient wood which used to be a royal deer park near Devizes in Wiltshire."
}