Gets or sets the widgets' caption (MK CA): a push button's label, or the ZapfDingbats character a check box or
radio button shows when on (4, a check mark, and l, a dot, by default); null writes none.
Buttons only.
public string? Caption { get; set; }
ISO 32000-2 §12.5.6.19, Table 192, and §12.7.5.2.