Post data with NavigateWithWebResourceRequest and BasicAuthenticationRequested

I use webview2 to post some form variables with navigatewithwebresourcerequest to a page:

`Public Sub Navigate(urlString As String, PostData As List(Of SharedLib.ValuePair)) Implements iWebBrowser.Navigate

    If mEdge.CoreWebView2 IsNot Nothing Then
        Dim strFormData As String = ""
        For Each itm In PostData
            strFormData &= itm.id & "=" & System.Web.HttpUtility.UrlEncode(itm.value) & "&"
        Next

        If strFormData <> "" Then
            strFormData = strFormData.Substring(0, strFormData.Length - 1)
            Dim bytedata As Byte() = System.Text.Encoding.UTF8.GetBytes(strFormData)

            Dim msPostData = New MemoryStream(bytedata.Length)
            msPostData.Write(bytedata, 0, bytedata.Length)
            msPostData.Seek(0, SeekOrigin.Begin)

            Dim webResouceRequest = mEdge.CoreWebView2.Environment.CreateWebResourceRequest(urlString, "POST", msPostData, "Content-Type: application/x-www-form-urlencoded")
            mEdge.CoreWebView2.NavigateWithWebResourceRequest(webResouceRequest)
        Else
            mEdge.Source = New Uri(urlString)
        End If

    Else
        murlString = urlString
        mPostData = PostData
    End If

End Sub`

This works.

If I post those form variables to a site with basic authenttication, it will fail. My basic authentication is setup as follows:

`Public Sub SetCredentials(ServerAddress As String, User As String, Password As String) Implements iWebBrowser.SetCredentials

    _ServerAddress = ServerAddress
    _User = User
    _Password = Password

    'setup handler, if not already done
    If _RequestFilterSet = False AndAlso mEdge.CoreWebView2 IsNot Nothing Then
        AddHandler mEdge.CoreWebView2.BasicAuthenticationRequested, AddressOf BasicAuthenticationRequested
        
        _RequestFilterSet = True
    End If

End Sub

Private Sub BasicAuthenticationRequested(sender As Object, e As CoreWebView2BasicAuthenticationRequestedEventArgs)

    If _ServerAddress <> "" AndAlso _User <> "" AndAlso _Password <> "" Then
        'requested site must be our website, preventing pushing password to other websites
        If e.Uri.ToLower.StartsWith(_ServerAddress.ToLower) Then
            e.Response.UserName = _User
            e.Response.Password = _Password
        End If
    End If

End Sub

`

The BasicAuthenticationRequested event is being triggered, but there are no form variables. Am I doing something wrong or is this a bug?

I solved it temporarily by disabling the basic authentication on the page, but this is not the solution.

Thanks
Paul