FloatingStatusWindow/Library/MainWindow.xaml

<snappingWindow:SnappingWindow x:Class="ChrisKaczor.Wpf.FloatingStatusWindow.MainWindow"
                               xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                               xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                               xmlns:snappingWindow="clr-namespace:ChrisKaczor.Wpf.Windows;assembly=ChrisKaczor.Wpf.Windows.SnappingWindow"
                               xmlns:controlBox="clr-namespace:ChrisKaczor.Wpf.Windows;assembly=ChrisKaczor.Wpf.Windows.ControlBox"
                               xmlns:controls="clr-namespace:ChrisKaczor.Wpf.Controls;assembly=ChrisKaczor.Wpf.Controls.HtmlTextBlock"
                               controlBox:ControlBox.HasMaximizeButton="False"
                               controlBox:ControlBox.HasMinimizeButton="False"
                               controlBox:ControlBox.HasSystemMenu="False"
                               Title="FloatingStatusWindow"
                               Height="250"
                               Width="400"
                               WindowStyle="None"
                               AllowsTransparency="True"
                               ResizeMode="CanResize"
                               Background="Transparent"
                               ShowInTaskbar="False"
                               x:ClassModifier="internal">

    <Border Name="BorderFull"
            BorderThickness="4,0,4,4"
            Background="Transparent"
            Margin="0">
        <Grid Background="Transparent">
            <Border Name="HeaderBorder"
                    Height="24"
                    VerticalAlignment="Top">
                <Grid>
                    <Label HorizontalAlignment="Stretch"
                           Name="HeaderLabel"
                           Margin="0,0,0,0"
                           HorizontalContentAlignment="Center"
                           VerticalContentAlignment="Center"
                           Padding="0">
                    </Label>
                    <Button Height="18"
                            Width="18"
                            HorizontalAlignment="Right"
                            Margin="0,0,5,0"
                            Click="HandleChangeAppearanceClick"
                            WindowChrome.IsHitTestVisibleInChrome="True"
                            Content="&#xE115;"
                            FontFamily="Segoe UI Symbol"
                            FontSize="12"
                            Padding="0">
                    </Button>
                </Grid>
            </Border>
            <Grid Name="ContentGrid">
                <controls:HtmlTextBlock Name="HtmlLabel"
                                        Foreground="White"
                                        HorizontalAlignment="Stretch"
                                        VerticalAlignment="Center"
                                        Margin="0,24,0,0" />
            </Grid>
        </Grid>
    </Border>
</snappingWindow:SnappingWindow>