Examine source code of Sound Spy

{
  "manifest_version": 2,
  "name": "Sound Spy",
  "version": "1.0",
  "description": "Tạo hiệu ứng âm thanh dựa trên nội dung trang web.",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "icons": {
    "16": "icon.png",
    "48": "icon.png",
    "128": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{48f7abe4-f61c-4b64-bb0a-d98f6d43471a}"
    }
  }
}