[initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.alwaysAllow] throws error 'Unsupported operation: add'

[r-durao-pvotal]

import 'package:flutter/material.dart';
import 'package:webviewx_plus/webviewx_plus.dart';

class IFrameSample extends StatefulWidget {
  const IFrameSample({
    required this.width,
    required this.height,
    super.key,
  });

  final double width;
  final double height;

  @override
  State<IFrameSample> createState() => _IFrameSampleState();
}

class _IFrameSampleState extends State<IFrameSample> {
  late WebViewXController webviewController;

  @override
  Widget build(BuildContext context) {
    return WebViewX(
      width: widget.width,
      height: widget.height,
      initialContent: '<h2> Loading </h2>',
      initialSourceType: SourceType.html,
      onWebViewCreated: (controller) => webviewController = controller
        ..loadContent(
          'https://google.com',
        ),
      initialMediaPlaybackPolicy: AutoMediaPlaybackPolicy.alwaysAllow,
    );
  }
}

This throws an error

│ ⛔ === UI ERROR ===
│ ⛔ Unsupported operation: add
│ ⛔ dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 288:49
throw_
│ ⛔ dart-sdk/lib/_internal/js_dev_runtime/private/js_array.dart 76:7
checkGrowable]
│ ⛔ dart-sdk/lib/_internal/js_dev_runtime/private/js_array.dart 82:5
add]
│ ⛔ webviewx_plus-0.3.3/lib/src/view/impl/web.dart 369:12
[_createIFrame]
│ ⛔ /webviewx_plus-0.3.3/lib/src/view/impl/web.dart 159:14
initState

am I missing a step?