//Makes window not show in App-Switcher (Alt+Tab)
private void OnLoaded(object sender, RoutedEventArgs routedEventArgs)
{
var wndHelper = new WindowInteropHelper(this);
var exStyle = NativeMethods.GetWindowLong(wndHelper.Handle, Gwl.Exstyle);
exStyle |= 0x00000080;
NativeMethods.SetWindowLongShadow(wndHelper.Handle, (int)Gwl.Exstyle, (IntPtr)exStyle);
}