Examine source code of Mario

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Mario",
  "manifest_version": 2,
  "description": "Mario is the excellent and the awesome game which bring our childhood memories back!!!\ni created to bring back back my childhood awesome memories back to my favorite  firefox browser!!\nEnjoy the theme!!"
}