[WinUI] Menu items changes in c# code doesn't change contextmenu with SecondWindow mode

[Jeric-X]

Describe the bug

MenuFlyoutName.Items.Add(new MenuFlyoutItem() { Text = "new added" });

changing MenuFlyou.Items doesn't change context menu
If set ContextMenuMode=PopupMenu or ActiveWindow, context menu does change.

Steps to reproduce the bug

change H.NotifyIcon.Apps.WinUI project
TrayIconView.xaml

    <tb:TaskbarIcon
        x:Name="TrayIcon"
        x:FieldModifier="public"
        IconSource="ms-appx:///Assets/Red.ico"
        ToolTipText="ToolTip"
        LeftClickCommand="{x:Bind ShowHideWindowCommand}"
        NoLeftClickDelay="True"
        ContextMenuMode="SecondWindow"
        >
        <tb:TaskbarIcon.ContextFlyout>


<!--  Changes here  -->
            <MenuFlyout AreOpenCloseAnimationsEnabled="False" x:Name="Menu">
                <MenuFlyoutItem Command="{x:Bind AddCommand}" Text="Add Item" />
<!--  Changes here  -->


                 <MenuFlyoutItem Command="{x:Bind ShowHideWindowCommand}" Text="Show/Hide Window" />
                <MenuFlyoutSeparator />
                <MenuFlyoutItem Command="{x:Bind ExitApplicationCommand}" Text="Exit" />
            </MenuFlyout>
        </tb:TaskbarIcon.ContextFlyout>
    </tb:TaskbarIcon>

TrayIconView.xaml.cs

    [RelayCommand]
    public void Add()
    {
        Menu.Items.Add(new MenuFlyoutItem() { Text = "new added" });
    }

Then click "Add Item"

Expected behavior

Like PopupMenu mode, A new Item was Added

Screenshots

No response

NuGet package version

2.0.108

Platform

WinUI

IDE

Visual Studio 2022

Windows Version

Windows 11

WindowsAppSDK Version

Other

WindowsAppSDK Type

Packaged

Manifest

No response

Additional context

No response

[Jeric-X]

The reason is that the real working MenuFlyout(and it's Items) is the second transparent window's property. Items in xaml is just for preparation.