WPF WindowChrome unwanted black shadow - Caused by SizeToContent="WidthAndHeight" - wpf

Question

I'm trying to create a custom popup window in WPF, but I can't seem to do it without a there being a black "drop shadow" around it. I'm using ContentControl for the body of it so that I can change the body for different popups.
I can remove the "shadow" by removing SizeToContent="WidthAndHeight", but then I don't have a window that adapts to it's content.
Here's the xaml
<Window x:Class="PriceFinding.Utility.Dialogs.Service.DialogWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:PriceFinding.Utility.Dialogs.Service"
mc:Ignorable="d"
SizeToContent="WidthAndHeight"
WindowStartupLocation="CenterScreen"
MinHeight="300" MinWidth="800"
Background="{StaticResource BrushPrimary}"
>
<WindowChrome.WindowChrome>
<WindowChrome CaptionHeight="50"/>
</WindowChrome.WindowChrome>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0" WindowChrome.IsHitTestVisibleInChrome="True" VerticalAlignment="Top" Background="{StaticResource BrushPrimaryDark}" Name="TitleBar" Height="35">
<StackPanel Orientation="Horizontal" HorizontalAlignment="Left">
<Image Source = "pf.ico" Height="20" Width="20" Margin="5,0" />
<Label Content="{Binding Title}" VerticalAlignment="Center" HorizontalAlignment="Left" FontSize="14"/>
</StackPanel>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Margin="0,0,5,0">
<Button
x:Name="MinButton"
Height="35" Width="35" Padding="0"
Command="{Binding MinimizeButton.MinimizeCommand}">
</Button>
<Button
x:Name="MaxButton"
Height="35" Width="35" Padding="0"
HorizontalAlignment="Left"
Command="{Binding MaximizeButton.MaximizeCommand}">
</Button>
<Button
x:Name="CloseButton"
Height="35" Width="35" Padding="0"
HorizontalAlignment="Right"
Command="{Binding CloseButton.CloseCommand}">
</Button>
</StackPanel>
</Grid>
<ContentControl Grid.Row="1" x:Name="ContentPresenter" Content="{Binding}"></ContentControl>
</Grid>
How can I get around this?

Answer 1

Here (or here, for the more daring) is a workaround!
This is quite a weird problem, but, indeed, running an event when the content is rendered:
ContentRendered="Window_OnContentRendered"
like so:
private void Window_OnContentRendered(object sender, EventArgs e)
{
InvalidateVisual();
}

Answer 2

InvalidateVisual does not remeasure content of window. Also no need to change the chrome.
This helped me:
protected override void OnContentRendered(EventArgs e)
{
base.OnContentRendered(e);
// Content of window may be black in case of SizeToContent is set.
// This eliminates the problem.
// Do not use InvalidateVisual because it may implicitly break your markup.
InvalidateMeasure();
}

Answer 3

You can set the GlassFrameThickness to zero:
<WindowChrome GlassFrameThickness="0"
CaptionHeight="0" />
And that should remove the drop shadow effect and it will also allow you to use the CornerRadius effect if you were interested.

Answer 4

This is caused by a bug in WPF.
See https://social.msdn.microsoft.com/Forums/vstudio/en-US/f51ba061-69e2-4c85-b77a-41307423c2bf/sizetocontentheight-windowstylenone-resizemodenoresize-weirdness?forum=wpf
For a workaround, you can refresh the view. InvalidateVisual did not work for me.
You can attach an event handler to the window like so:
Background="{StaticResource BrushPrimary}" Activated="Window_Activated" StateChanged="Window_Activated"
Then, in the code behind:
private void Window_Activated(object sender, EventArgs e)
{
this.SizeToContent = SizeToContent.Manual;
this.SizeToContent = SizeToContent.WidthAndHeight;
}