AngleSharp by Florian Rappl

<PackageReference Include="AngleSharp" Version="0.2.0" />

.NET API 372,224 bytes

 HTMLOptGroupElement

namespace AngleSharp.DOM.Html { public class HTMLOptGroupElement : HTMLElement { public const string Tag = "optgroup"; public string Label { get { return GetAttribute("label"); } set { SetAttribute("label", value); } } public bool Disabled { get { return GetAttribute("disabled") != null; } set { SetAttribute("disabled", value ? string.Empty : null); } } protected internal override bool IsSpecial => false; public HTMLOptGroupElement() { _name = "optgroup"; } } }