Examine source code of Google Docs Offline V2

{
  "manifest_version": 2,
  "name": "Google Docs Offline",
  "version": "1.3",
  "description": "Access Google Docs offline.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": {
      "32": "icons/logo_32.png",
      "64": "icons/logo_64.png",
      "128": "icons/logo_128.png"
    },
    "default_popup": "popup.html"
  },
  "icons": {
    "32": "icons/logo_32.png",
    "64": "icons/logo_64.png",
    "128": "icons/logo_128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{4d341281-3dc3-4e67-a95a-01d66a688c58}"
    }
  }
}