Examine source code of The Super Mario Bros

{
  "name": "The Super Mario Bros",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "The Super Mario Bros.jpg"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(255, 245, 59, 1)",
      "toolbar": "rgba(0, 0, 0, 0)",
      "toolbar_field": "rgba(255, 255, 255, 0.64)",
      "toolbar_field_text": "rgba(176, 67, 94, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{580e7d46-a771-4534-a206-10c1187ebc92}"
    }
  }
}