Examine source code of CSS Spider

{
  "short_name": "CSS-Spider",
  "name": "CSS Spider",
  "version": "1.3",
  "description": "The fastest and easiest way to check, copy and edit CSS",
  "manifest_version": 2,
  "browser_action": {
    "default_title": "Css Spider"
  },
  "icons": {
    "128": "logo.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "permissions": [
    "activeTab",
    "http://*/",
    "https://*/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{b52ae68e-7aa5-4caa-9eb4-e37f9783d26e}"
    }
  }
}