Examine source code of InstaAudio Downloader

{
  "manifest_version": 3,
  "name": "InstaAudio Downloader",
  "version": "3.0.0",
  "description": "Download & play Instagram DM voice messages instantly.",
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "permissions": [
    "webRequest",
    "downloads",
    "activeTab",
    "tabs"
  ],
  "host_permissions": [
    "*://*.fbcdn.net/*",
    "*://*.cdninstagram.com/*",
    "*://*.fbsbx.com/*",
    "*://*.facebook.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "page": "background.html"
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.instagram.com/direct/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "instaaudio@example.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  }
}