How to switch active window contain WebView2 from modal window?

Hello,

I'm using WebView2 in content of DocumentWindow/ToolWindow.

When I tried to switch active window from modal window, below exception occured.

Would you please tell me the workaround?

Is this problem of WebView2 side?

Exception

System.ArgumentException
  HResult=0x80070057
  Message=Value does not fall within the expected range.
  Source=Microsoft.Web.WebView2.Core
  Stack trace:
   at Microsoft.Web.WebView2.Core.Raw.ICoreWebView2Controller.MoveFocus(COREWEBVIEW2_MOVE_FOCUS_REASON reason)
   at Microsoft.Web.WebView2.Core.CoreWebView2Controller.MoveFocus(CoreWebView2MoveFocusReason reason)
   at Microsoft.Web.WebView2.Wpf.WebView2.TabIntoCore(TraversalRequest request)
   at ActiproSoftware.Internal.NH.LXA(UIElement  )
   at ActiproSoftware.Internal.NH.aXR(UIElement  )
   at ActiproSoftware.Internal.NH.<>c__DisplayClass7_0.K88()
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Window.ShowHelper(Object booleanBox)
   at System.Windows.Window.ShowDialog()
   at ActiproSoftware.ProductSamples.DockingSamples.Demo.SimpleIde.MainControl.OnSubWindowMenuClick(Object sender, RoutedEventArgs e) in C:\Users\[User Name]\Documents\Actipro Software\WPF-Controls\v21.1.3\SampleBrowser\ProductSamples\DockingSamples\Demo\SimpleIde\MainControl.xaml.cs:line 606
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.Controls.MenuItem.InvokeClickAfterRender(Object arg)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at ActiproSoftware.SampleBrowser.App.Main()

My sample source code

(based on SampleBrowser\ProductSamples\DockingSamples\Demo\SimpleIde)

MainControl.xaml(1)
- Add ToolWindow contains WebView2 to ToolWindowContainer.

<sampleBrowser:ProductItemControl
~~
    namespace:Microsoft.Web.WebView2.Wpf;assembly=Microsoft.Web.WebView2.Wpf"
~~~~
    >

                        <docking:ToolWindowContainer>
                            <docking:ToolWindow
                                x:Name="WebView2ToolWindow"
                                Title="WebView2">
                                <wv2:WebView2 docking:InteropFocusTracking.IsEnabled="True" Source="https://www.microsoft.com" />

                            </docking:ToolWindow>
~~~~

SubWindow.xaml (Create new)

<Window
    x:Class="ActiproSoftware.ProductSamples.DockingSamples.Demo.SimpleIde.SubWindow"
    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"
    Title="SubWindow"
    Width="800"
    Height="450"
    mc:Ignorable="d">
    <Grid>
        <Button Click="Button_Click" Content="Active" />
    </Grid>
</Window>

SubWindow.xaml.cs (Create new)

using System;
using System.Windows;

namespace ActiproSoftware.ProductSamples.DockingSamples.Demo.SimpleIde
{
    /// <summary>
    /// SubWindow.xaml の相互作用ロジック
    /// </summary>
    public partial class SubWindow : Window
    {
        public Action ActiveAction { get; set; }

        public SubWindow()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            ActiveAction?.Invoke();
        }
    }
}

MainControl.xaml(2)

- Add menu item to show SubWindow.

<Menu>
    <MenuItem Header="_File">
        <MenuItem Click="OnSubWindowMenuClick" Header="Sub Window" />

MainControl.xaml.cs

- Add event handler

private void OnSubWindowMenuClick(object sender, RoutedEventArgs e)
{
    var w = new SubWindow();
    w.ActiveAction = () => WebView2ToolWindow.IsActive = true;
    w.ShowDialog();
}