How to hide a menu item in the built-in context menu of WinForms Docking Manager?

//To hide the "TabbedDocument" option in the context menu for the control "panel1"
void dockingManager1_DockContextMenu(object sender, Syncfusion.Windows.Forms.Tools.DockContextMenuEventArgs arg)
{
    if (arg.Owner == this.panel1)
        arg.ContextMenu.ParentBarItem.Items[2].Visible = false;
}

'To hide the "TabbedDocument" option in the context menu for the control "panel1"
Private Sub dockingManager1_DockContextMenu(ByVal sender As Object, ByVal arg As Syncfusion.Windows.Forms.Tools.DockContextMenuEventArgs)
    If arg.Owner = Me.panel1 Then
        arg.ContextMenu.ParentBarItem.Items(2).Visible = False
    End If
End Sub