MainPage.xaml

<Page
    x:Class="ExtensionSample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:ExtensionSample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
        <TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" TextAlignment="Center" Style="{ThemeResource SubtitleTextBlockStyle}" TextWrapping="WrapWholeWords" TextTrimming="None" Text="Close this, and go to Aurora Music-Settings, switch 'Debug Mode' to 'On' and refresh, then you can see this appear at Lyric Extension ComboBox"/>
    </Grid>
</Page>