Sometimes click something in The WebView2 Page will open a new Microsoft Edge Window,could we show it in the Webview2 replace open a new window?

You could use CoreWebView2.NewWindowRequested to set whether to open a new window.

To completely suppress the popup, set e.Handled = true;
To show the popup content in the same window, set e.NewWindow = (CoreWebView2)sender;
To open in another specific instance, set e.NewWindow to the other CoreWebView2 instance.

For example:

The code of xaml:

<Window x:Class="WpfApp1.MainWindow"  
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"  
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"  
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"  
        xmlns:local="clr-namespace:WpfApp1"  
        mc:Ignorable="d"  
        xmlns:wv2="clr-namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf"  
        Title="MainWindow" Height="450" Width="800" Loaded="Window_Loaded">  
    <DockPanel>  
    <DockPanel DockPanel.Dock="Top">  
        <Button x:Name="ButtonGo" DockPanel.Dock="Right" Click="ButtonGo_Click" Content="Go"/>  
        <TextBox Name = "addressBar"/>  
    </DockPanel>  
    <wv2:WebView2 Name = "webView"  Source = "https://www.bing.com/" />  
</DockPanel>  
</Window>  

The code of xaml.cs:

using Microsoft.Web.WebView2.Core;  
using System.Windows;  
  
namespace WpfApp1  
{  
  public partial class MainWindow : Window  
  {  
    public MainWindow()  
    {  
      InitializeComponent();  
    }  
    private void ButtonGo_Click(object sender, RoutedEventArgs e)  
    {  
      if (webView != null && webView.CoreWebView2 != null)  
      {  
        webView.CoreWebView2.Navigate(addressBar.Text);  
      }  
    }  
    private void webView_NewWindowRequested(object sender, CoreWebView2NewWindowRequestedEventArgs e)  
    {  
      e.NewWindow = (CoreWebView2)sender;  
      //e.Handled = true;  
    }  
    private async void Window_Loaded(object sender, RoutedEventArgs e)  
    {  
      await webView.EnsureCoreWebView2Async();  
      webView.CoreWebView2.NewWindowRequested += webView_NewWindowRequested;  
    }  
  }  
}  

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