If you currently need an empty NonSelfClosingHtmlElement (e.g. for <select>) it is required to create a class which extends the AbstractNonSelfClosingHtmlElement or use HtmlElement and add empty text.
For normal HtmlElements you can use new HtmlElement("foobar").
It would be nice to have a possiblity to create a NonSelfClosingHtmlElement like new NonSelfClosingHtmlElement("foobar");
currently those DOM wrappers are only to be used internally by the handler infrastructure namely the markup builders.
they are currently not indented to be used for component rendering - until we decide to to so.