webview_flutter_web is not working in flutter Web

I'm using webview_flutter_web library for loading the url in webview (for flutter web-build), when i'm trying to load to load https://www.youtube.com/, it's not loading showing error as refused to connect. please support to resolve this issue thank you in advance.

import 'dart:async';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:webview_flutter_platform_interface/webview_flutter_platform_interface.dart';
import 'package:webview_flutter_web/webview_flutter_web.dart';

class WebViewExample extends StatefulWidget {
  const WebViewExample({Key? key}) : super(key: key);

  @override
  _WebViewExampleState createState() => _WebViewExampleState();
}

class _WebViewExampleState extends State<WebViewExample> {
  late double screenWidth;
  late double screenHeight;
  final PlatformWebViewController _controller = PlatformWebViewController(
    const PlatformWebViewControllerCreationParams(),
  )..loadRequest(
      LoadRequestParams(
        
         uri: Uri.parse('https://www.youtube.com/'),
         

      ),
    );

  @override
  Widget build(BuildContext context) {
    screenWidth = MediaQuery.of(context).size.width;
    screenHeight = MediaQuery.of(context).size.height;

    if (screenWidth >= 1024) {
      screenWidth = screenWidth * 0.6;
    } else if (screenWidth >= 768 && screenWidth <= 1024) {
      screenWidth = screenWidth * 0.8;
    } else if (screenWidth >= 600) {
      screenWidth = screenWidth * 0.5;
    } else {
      screenWidth = screenWidth;
    }
    return Scaffold(
      appBar: AppBar(
        title: const Text('Flutter WebView example'),
      
      ),
      body: Center(
        child: SizedBox(
          width: screenWidth,
          height: screenHeight,
          child: PlatformWebViewWidget(
            PlatformWebViewWidgetCreationParams(controller: _controller),
          ).build(context),
        ),
      ),
    );
  }
}