WPF C#

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        x:Class="AboutDialog" MouseRightButtonDown="AboutDialog_MouseRightButtonDown"
        Title="About WPF Unleashed" SizeToContent="WidthAndHeight"
        Background="OrangeRed">
  
    
      WPF
    
    
    
    
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    test
  

//File:Window.xaml.cs
using System;
using System.Windows;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Controls;
public partial class AboutDialog : Window
{
    public AboutDialog()
    {
        InitializeComponent();
    }
    void AboutDialog_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
    {
        Console.WriteLine("Source = " + e.Source.GetType().Name);
        Console.WriteLine("OriginalSource = " + e.OriginalSource.GetType().Name + " @ " + e.Timestamp);
        Control source = e.Source as Control;
        if (source.BorderThickness != new Thickness(5))
        {
            source.BorderThickness = new Thickness(5);
            source.BorderBrush = Brushes.Black;
        }
        else
            source.BorderThickness = new Thickness(0);
    }
}