Examine source code of Xdebug Cookie

{
  "manifest_version": 2,
  "name": "Xdebug Cookie",
  "version": "3.3.1",
  "description": "Xdebug Cookie",
  "homepage_url": "https://github.com/lurkker/xdebug-cookie",
  "icons": {
    "64": "icons/bug-green-64.png",
    "128": "icons/bug-green-128.png"
  },
  "permissions": [
    "tabs",
    "cookies",
    "storage",
    "<all_urls>"
  ],
  "browser_action": {
    "default_icon": {
      "64": "icons/bug-light-64.png",
      "128": "icons/bug-light-128.png"
    },
    "default_title": "Xdebug (off)"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "applications": {
    "gecko": {
      "id": "xdebug-cookie@lurkker"
    }
  },
  "background": {
    "scripts": [
      "xdebug.js"
    ]
  }
}