private void RadRibbonView_PreviewKeyDown(object sender, KeyEventArgs e)
{
    var ribbon = (RadRibbonView)sender;
    if (ribbon.IsMinimized && (e.Key == Key.Left || e.Key == Key.Right))
    {
        var focusedHeader = Keyboard.FocusedElement as RadRibbonTab;
        if (focusedHeader != null && ribbon.SelectedItem != focusedHeader)
        {
            ribbon.SelectedItem = focusedHeader;
            e.Handled = false;
        }
    }
}