<UserControl x:Class="PowerCalculations.UI.WPF.UserControls.TestUserControl"             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"              xmlns:local="clr-namespace:PowerCalculations.UI.WPF.UserControls"             mc:Ignorable="d"              d:DesignHeight="300" d:DesignWidth="300">    <Grid>                </Grid></UserControl>