Just setting the following resources xaml as application dictionary will crash the editor when it gets closed:

<ResourceDictionary

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:noesis="clr-namespace:NoesisGUIExtensions;assembly=Noesis.GUI.Extensions"

xmlns:local="clr-namespace:Materials">

<ResourceDictionary.MergedDictionaries>

<ResourceDictionary Source="pack://application:,,,/Noesis.GUI.Extensions;component/Theme/NoesisTheme.DarkBlue.xaml"/>

</ResourceDictionary.MergedDictionaries>

<ImageBrush x:Key="NoiseImageBrush" ImageSource="/Game;component/Materials/fill-blue.png">

<noesis:Brush.Shader>

<local:Noise Color="Red"/>

</noesis:Brush.Shader>

</ImageBrush>

</ResourceDictionary>

The crash happens during Shutdown when destroying the application resources, because it tries to use the TypeClass created for the Material that is already destroyed.