Avalonia/tests/BuildTests/BuildTests.WpfHybrid/UserControl1.xaml

<UserControl x:Class="BuildTests.WpfHybrid.UserControl1"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             mc:Ignorable="d"
             d:DesignHeight="300" d:DesignWidth="300">
  <Grid>
    <TextBlock Text="UserControl1" />
  </Grid>
</UserControl>