Examine source code of IP Geolocator

{
  "name": "IP Address & Geolocation",
  "version": "2.1.0",
  "manifest_version": 2,
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "description": "Shows your IPv4 & IPv6 address and also geolocational informations about your IP addresses.",
  "background": {
    "page": "background.html"
  },
  "minimum_chrome_version": "25",
  "permissions": [
    "notifications"
  ],
  "browser_action": {
    "default_icon": "img/icon.png",
    "default_popup": "popup.html",
    "default_title": "IP Address & Geolocation"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "applications": {
    "gecko": {
      "id": "ipgeolocator@aykutcevik.com"
    }
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": false,
    "chrome_style": false,
    "open_in_tab": true
  }
}