Examine source code of Marionette Inspector

{
  "name": "Marionette Inspector",
  "version": "0.9.2resigned1",
  "description": "A devtool for Marionette",
  "author": "Jason Laster",
  "minimum_chrome_version": "22.0",
  "icons": {
    "16": "img/marionette-16.png",
    "48": "img/marionette-48.png",
    "128": "img/marionette-128.jpg"
  },
  "manifest_version": 2,
  "devtools_page": "inspector.html",
  "background": {
    "scripts": [
      "js/background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*",
        "file://*/*"
      ],
      "js": [
        "js/marionette_contentscript.js"
      ],
      "css": [
        "css/agent.css"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    "js/lib/*",
    "js/agent/*"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "permissions": [
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5f57f8d4-b1c5-4342-9633-34e2eadc6835}"
    }
  }
}