Examine source code of Volume Balance

{
  "manifest_version": 3,
  "name": "Volume Balance",
  "version": "1.1.2",
  "description": "Automatically levels out loud and quiet audio passages on every website. Set & forget.",
  "author": "Adelvo",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "host_permissions": [
    "https://api.keygen.sh/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle",
      "all_frames": true
    }
  ],
  "action": {
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "volume-balance@adelvo.io",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo"
        ]
      }
    }
  }
}