WPF

<RichTextBox 
    x:Key="rtfBox"
    SpellCheck.IsEnabled = "False"
    ContextMenuService.ShowOnDisabled="True"    
    ContextMenu="{StaticResource rtfBoxContextMenu}">    
  </RichTextBox>

<ContextMenu x:Key="rtfBoxContextMenu">
  <MenuItem Command="Copy"/>
  <MenuItem Command="Cut"/>
  <MenuItem Command="Paste"/>
  <Separator/>
  <MenuItem Command="My:MyCommands.ToggleSpellChecker" IsCheckable="true"/>
</ContextMenu>

<RichTextBox
  x:Key="rtfBox"
  HorizontalScrollBarVisibility="Auto" 
  VerticalScrollBarVisibility="Auto" 
  HorizontalAlignment="Stretch"
  VerticalAlignment="Stretch"
 />

<Window x:Class="BidiFix.SandBox.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    mc:Ignorable="d" 
 Title="Window1" AllowsTransparency="True" Focusable="False" ShowActivated="False" ShowInTaskbar="False"
  SizeToContent="Width" Height="24" Topmost="True" Padding="2"
  WindowStyle="None" Background="Transparent" >

  <Border>  
   <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Margin="2">
    <Button Command="Copy" Context="Copy"/>
    <Button Command="Cut" Context="Cut"/>
    <Button Command="Paste" Context="Paste"/>
    </StackPanel>
  </Border>
</Window>

RichTextBox rtfBox = GetTheBox();
Window1 win = new Window1();
win.Show();