/// <summary>
/// Specifies that only a portion of the window's client area
/// should be used in the window's thumbnail.
/// </summary>
/// <param name="hwnd">The window.</param>
/// <param name="clipRect">The rectangle that specifies the clipped region.</param>
private static void SetThumbnailClip(this Form form, Rectangle clipRect)
{
//Example: SetThumbnailClip(this, new Rectangle(button.Location, button.Size));
Rect rect = new Rect(clipRect.Left, clipRect.Top, clipRect.Right, clipRect.Bottom);
HResult setThumbnailClipResult = TaskbarList.SetThumbnailClip(form.Handle, ref rect);
setThumbnailClipResult.ThrowIf();
}