Examine source code of Audio Boost – Smart Volume Max

{
  "manifest_version": 3,
  "name": "Audio Boost 400% – Smart Volume Max",
  "version": "1.4.0",
  "description": "Boost tab volume up to 400%! Smart Volume Max gives you full control over sound with a clean UI and instant audio amplification.",
  "browser_specific_settings": {
    "gecko": {
      "id": "{b0aad83c-24c6-484b-ac91-9afae1f1358c}",
      "strict_min_version": "128.0"
    },
    "gecko_android": {
      "id": "{b0aad83c-24c6-484b-ac91-9afae1f1358c}",
      "strict_min_version": "128.0"
    }
  },
  "permissions": [
    "alarms",
    "activeTab",
    "webNavigation",
    "scripting",
    "storage"
  ],
  "host_permissions": [
    "*://*/*"
  ],
  "action": {
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "worker.js"
    ]
  },
  "icons": {
    "16": "/resource/ico_16.png",
    "48": "/resource/ico_48.png",
    "64": "/resource/ico_64.png",
    "128": "/resource/ico_128.png"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "*.js"
      ],
      "matches": [
        "https://*/*"
      ]
    }
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "cscr.js",
        "jquery.min.js"
      ],
      "run_at": "document_start"
    }
  ]
}