How-to-show-the-filter-status-message-in-wpf-datagrid breaks if used in more than one SfDataGrid

[CADbloke]

it throws a System.Windows.Markup.XamlParseException - System.ArgumentException: PropertyMetadata is already registered for type 'FilterStatusBar' at the ctor

at https://github.com/SyncfusionExamples/WPF-DataGrid-Samples/blob/main/How-to-show-the-filter-status-message-in-wpf-datagrid/WPF/CS/StatusBar/FilterStatusBar.cs#L91

I replaced

/// <summary>
/// Initializes the <see cref="FilterStatusBar"/> class.
/// </summary>
public FilterStatusBar()
{
    DefaultStyleKeyProperty.OverrideMetadata(typeof(FilterStatusBar), new FrameworkPropertyMetadata(typeof(FilterStatusBar)));          
}

with

private static bool alreadyRegistered = false;

/// <summary>
/// Initializes the <see cref="FilterStatusBar"/> class.
/// </summary>
public FilterStatusBar()
{
    if (!alreadyRegistered)      
    {
        DefaultStyleKeyProperty.OverrideMetadata(typeof(FilterStatusBar), new FrameworkPropertyMetadata(typeof(FilterStatusBar)));
        alreadyRegistered = true;
    }
}