SgmlReader is a .NET library that is handy for converting SGML content (like HTML and OFX) into well formed XML via XmlReader, XmlDocument, XDocument or XPathDocument. It runs on Windows and Linux using Mono.
Straight copy of the code base, converted to use netstandard2.0 for use in core 3.1 app. Original source located at https://github.com/MindTouch/SGMLReader