Examine source code of Volley extension

{
  "manifest_version": 2,
  "name": "Volley extension",
  "description": "Volley lets you give fast, easy feedback for your website.",
  "version": "2.0.3",
  "permissions": [
    "<all_urls>",
    "tabs",
    "activeTab",
    "tabCapture",
    "cookies",
    "storage",
    "desktopCapture",
    "*://*.meetvolley.com/"
  ],
  "web_accessible_resources": [
    "static/**/*",
    "mic.html",
    "mic.js"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "icons": {
    "16": "icon-16.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": true,
      "js": [
        "main.js"
      ],
      "css": [
        "static/css/main.css"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "production-extension@meetvolley.com"
    }
  },
  "browser_action": {}
}