Examine source code of AntiID

{
  "manifest_version": 2,
  "name": "AntID",
  "version": "2.1",
  "description": "When prompted with ID age-verification, instead of giving over your information to Google, you will be shown the actual video instead. A very simple extension that creates an iframe element with the YTAPI's API.",
  "content_scripts": [
    {
      "matches": [
        "https://*.youtube.com/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{ace92219-3ecd-4986-845c-3d25a65eddfe}"
    }
  }
}