Examine source code of Super Mario898

{
  "icons": {
    "128": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Super Mario World Retro Game Play No Download"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "description": "Super Mario World Play Retro Game on Your Firefox Window",
  "name": "Super Mario World Retro Game",
  "manifest_version": 2,
  "permissions": [
    "activeTab"
  ],
  "update_url": "https://clients2.google.com/service/update2/crx",
  "version": "1.0.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "{e048e95a-6f2a-43df-9dac-fe1e97a65323}"
    }
  }
}