MainWindow.xaml

<windowex:WindowEx
    x:Class="BatteryTracker.MainWindow"
    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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:tb="using:H.NotifyIcon" xmlns:windowex="using:WinUIEx"
    MinWidth="500" MinHeight="200"
    PersistenceId="MainWindow"
    mc:Ignorable="d">

    <Window.SystemBackdrop>
        <MicaBackdrop />
    </Window.SystemBackdrop>

    <tb:TaskbarIcon
        x:Name="TrayIcon"
        ContextMenuMode="PopupMenu"
        LeftClickCommand="{StaticResource DisplayBatteryInfoCommand}"
        NoLeftClickDelay="True" ToolTipText="Battery Tracker"
        Visibility="Visible">
        <tb:TaskbarIcon.IconSource>
            <tb:GeneratedIconSource
                BackgroundType="Rectangle" FontFamily="Arial" FontWeight="SemiBold"
                Foreground="White" Text="99" />
        </tb:TaskbarIcon.IconSource>
        <tb:TaskbarIcon.ContextFlyout>
            <MenuFlyout>
                <MenuFlyoutItem Command="{StaticResource OpenSettingsCommand}" />
                <MenuFlyoutItem Command="{StaticResource ExitApplicationCommand}" />
            </MenuFlyout>
        </tb:TaskbarIcon.ContextFlyout>
    </tb:TaskbarIcon>
</windowex:WindowEx>