Examine source code of Nipsto URL Shortener

{
  "manifest_version": 2,
  "name": "Nipsto URL Shortener",
  "description": "Shorten URLs quickly using Nipsto.com",
  "version": "1.2",
  "permissions": [
    "tabs",
    "storage"
  ],
  "homepage_url": "https://nipsto.com",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_icon": "icons/icon48.png",
    "default_title": "Nipsto",
    "default_popup": "popup/nipsto.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d0316520-db48-4b68-8ecc-31710fa68861}"
    }
  }
}