How can I delete the header of a website on Flutter WebView (latest version)?

edit

You can use the following code to remove the header of a website on Flutter WebView:

class MyWebView extends StatelessWidget {
  final String url;

  MyWebView({required this.url});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: WebView(
        initialUrl: url,
        javascriptMode: JavascriptMode.unrestricted,
        onPageFinished: (String url) {
          removeHeader(context);
        },
      ),
    );
  }

  void removeHeader(BuildContext context) async {
    String removeHeaderJS = '''
      javascript:(function() {
        var header = document.getElementsByTagName('header')[0];
        header.style.display = 'none';
      })();
    ''';

    await Future.delayed(Duration(milliseconds: 500));
    await (await WebView.platformViewsRegistry.getPlatformViewsController((context.findRenderObject() as RenderBox).parentData!.size!.toRect())).evaluateJavascript(removeHeaderJS);
  }
}

In this code, we are using the Javascript getElementsByTagName method to get the first header element on the page and then setting its display property to none to hide it. We are calling the removeHeader method when the page has finished loading using the onPageFinished callback of the WebView. Finally, we are using the evaluateJavascript method to execute the removeHeaderJS code on the WebView.