onPageFinished method
Implementation
void onPageFinished(String url) {
if (finished) return;
final Uri? uri = Uri.tryParse(url);
if (uri == null || !uri.path.toLowerCase().contains("/ipg/verify")) return;
if (uri.queryParameters["done"] != "true" || uri.queryParameters["additionalData"] == null) return;
_finish(uri.queryParameters["additionalData"]!);
}