<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:ModernWpf.Controls">

    <ResourceDictionary.MergedDictionaries>
        <ResourceDictionary Source="/ModernWpf;component/Styles/ContextMenu.xaml" />
    </ResourceDictionary.MergedDictionaries>

    <Style TargetType="local:MenuFlyoutPresenter" BasedOn="{StaticResource ContextMenuStyleBase}">
        <Setter Property="IsDefaultShadowEnabled" Value="{DynamicResource {x:Static SystemParameters.DropShadowKey}}" />
        <Setter Property="HasDropShadow" Value="{Binding IsDefaultShadowEnabled, RelativeSource={RelativeSource Self}}" />
    </Style>

</ResourceDictionary>