seb-win-refactoring/SafeExamBrowser.UserInterface/Controls/TaskbarButton.xaml

<UserControl x:Class="SafeExamBrowser.UserInterface.Controls.TaskbarButton"
             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:SafeExamBrowser.UserInterface.Controls"
             mc:Ignorable="d" 
             d:DesignHeight="40" d:DesignWidth="40">
    <Grid>
        <Button x:Name="Button" Background="#00000000" BorderThickness="0" Click="Button_Click" Padding="5">
            <Image x:Name="IconImage" />
        </Button>
    </Grid>
</UserControl>