Dead Simple HTML Sanitizer

<UserControl x:Class="DemoApp.XmlViewer"
             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"
             xmlns:xmlstack="clr-namespace:System.Xml;assembly=System.Xml" mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
    <UserControl.Resources>
        <SolidColorBrush Color="Blue" x:Key="xmlValueBrush"/>
        <SolidColorBrush Color="Red" x:Key="xmAttributeBrush"/>
        <SolidColorBrush Color="DarkMagenta" x:Key="xmlTagBrush"/>
        <SolidColorBrush Color="Blue" x:Key="xmlMarkBrush"/>

        <DataTemplate x:Key="attributeTemplate">
            <StackPanel Orientation="Horizontal" 
                        Margin="3,0,0,0" HorizontalAlignment="Center">
                <TextBlock Text="{Binding Path=Name}" 
                           Foreground="{StaticResource xmAttributeBrush}"/>
                <TextBlock Text="=&quot;" 
                           Foreground="{StaticResource xmlMarkBrush}"/>
                <TextBlock Text="{Binding Path=Value}" 
                           Foreground="{StaticResource xmlValueBrush}"/>
                <TextBlock Text="&quot;" 
                           Foreground="{StaticResource xmlMarkBrush}"/>
            </StackPanel>
        </DataTemplate>

        <Style TargetType="{x:Type TreeViewItem}">
            <Setter Property="IsExpanded" Value="True"/>
        </Style>

        <HierarchicalDataTemplate x:Key="treeViewTemplate" 
                                  ItemsSource="{Binding XPath=child::node()}">
            <StackPanel Orientation="Horizontal" Margin="3,0,0,0" 
                        HorizontalAlignment="Center">
                <TextBlock Text="&lt;" HorizontalAlignment="Center" 
                           Foreground="{StaticResource xmlMarkBrush}" 
                           x:Name="startTag"/>

                <TextBlock Text="{Binding Path=Name}"
                    Margin="0"
                    HorizontalAlignment="Center"
                    x:Name="xmlTag"
                    Foreground="{StaticResource xmlTagBrush}"/>

                <ItemsControl
                    ItemTemplate="{StaticResource attributeTemplate}"
                    ItemsSource="{Binding Path=Attributes}"
                    HorizontalAlignment="Center">
                    <ItemsControl.ItemsPanel>
                        <ItemsPanelTemplate>
                            <StackPanel Orientation="Horizontal"/>
                        </ItemsPanelTemplate>
                    </ItemsControl.ItemsPanel>
                </ItemsControl>

                <TextBlock Text="&gt;" HorizontalAlignment="Center" 
                           Foreground="{StaticResource xmlMarkBrush}" 
                           x:Name="endTag"/>
            </StackPanel>

            <HierarchicalDataTemplate.Triggers>
                <DataTrigger Binding="{Binding NodeType}">
                    <DataTrigger.Value>
                        <xmlstack:XmlNodeType>Text</xmlstack:XmlNodeType>
                    </DataTrigger.Value>
                    <Setter Property="Text" Value="{Binding InnerText}" 
                            TargetName="xmlTag"/>
                    <Setter Property="Foreground" Value="Blue" 
                            TargetName="xmlTag"/>
                    <Setter Property="Visibility" Value="Collapsed" 
                            TargetName="startTag"/>
                    <Setter Property="Visibility" Value="Collapsed" 
                            TargetName="endTag"/>
                </DataTrigger>

                <DataTrigger Binding="{Binding HasChildNodes}" Value="False">
                    <Setter Property="Text" Value="/&gt;" TargetName="endTag"/>
                </DataTrigger>
            </HierarchicalDataTemplate.Triggers>
        </HierarchicalDataTemplate>
    </UserControl.Resources>

    <Grid>
        <TreeView Grid.Row="2" Grid.ColumnSpan="2" Name="xmlTree" 
                  ItemTemplate="{StaticResource treeViewTemplate}"/>
    </Grid>
</UserControl>