Webview does not open popup - Windows Phone 8.1

Question

I’m trying to get an authentication through a URL, up to there everything traquilo. But on the site, which I’m trying to authenticate, it is possible to log in with facebook but, by using this alternative, instead of the facebook login/authorization page appearing on the component itself (Webview) it calls the default OS browser, which means the authentication won’t work. My question is, how to make him open this facebook popup in the component itself? Thank you.

C#

private void wvwTeste_Loaded(object sender, RoutedEventArgs e)
{
    string _clientId = "123456";
    wvwTeste.Navigate(new Uri("https://api.teste.com/oauth/?" +
                                                    "response_type=code&" +
                                                    "redirect_uri=https://localhost/&" +
                                                    "client_id=" + _clientId + "&" +
                                                    "scope=read_public,write_public&" +
                                                    "state=768uyFys", UriKind.RelativeOrAbsolute));
}

XAML:

<Grid>
    <WebView x:Name="wvwTeste"
             HorizontalAlignment="Stretch"
             VerticalAlignment="Stretch"
             ScrollViewer.ZoomMode="Disabled"
             ScrollViewer.VerticalScrollBarVisibility="Disabled"
             Visibility="Visible" 
             NavigationCompleted="wvwTeste_NavigationCompleted" 
             Loaded="wvwTeste_Loaded" />
</Grid>