Binding issues with ContextMenu and CompositeCollection

Bug explanation

I have XAML Binding Failures with MenusAndToolBars.xaml if I change the lines https://github.com/MaterialDesignInXAML/MaterialDesignInXamlToolkit/blob/master/MainDemo.Wpf/MenusAndToolBars.xaml#L355-L360 with the follwogin content:

<ContextMenu>
  <ContextMenu.ItemsSource>
    <CompositeCollection>
      <MenuItem Header="Hello World" />
      <MenuItem Header="Clickety Click">
        <MenuItem Header="Clackety Clack" />
      </MenuItem>
    </CompositeCollection>
  </ContextMenu.ItemsSource>
</ContextMenu>

saying:

Severity Count Data Context Binding Path Target Target Type Description File Line Project
Error 2 null (0) MenuItem.Height Double Cannot find source: RelativeSource FindAncestor, AncestorType='System.Windows.Controls.Primitives.MenuBase', AncestorLevel='1'.

Do you have an idea how to fix this issue?

Version

4.9.0

从 MainDemo.Wpf/MenusAndToolBars.xaml 的第355-360行开始，使用提供的 ContextMenu 和 CompositeCollection 标记重现两个绑定失败。检查在此配置中 MenuItem.Height 如何解析其 MenuBase 祖先。示例不再报告 Cannot find source binding 绑定错误即表示完成。