chromium/chrome/test/data/web_apps/subapps_isolated_app/.well-known/manifest.webmanifest

{
    "name": "Sub apps test app",
    "id": "/",
    "version": "1.0.0",
    "scope": "/",
    "short_name": "Sub apps app",
    "icons": [{
      "src": "/subapps_icon.png",
      "sizes": "230x230",
      "type": "image/png",
      "purpose": "any maskable"
      }],
    "start_url": "/",
    "display": "standalone",
    "background_color": "#0000FF",
    "theme_color": "#000077",
    "permissions_policy": {
      "cross-origin-isolated": ["self"],
      "sub-apps": ["self"]
    }

}