load_html(+Source,
-ListOfContent, :Options)dialect(HTMLDialect),
where HTMLDialect is html4 or html5
(default), depending on the Prolog flag html_dialect. Both
imply the option shorttag(false). The option dtd(DTD)
is passed, where DTD is the HTML DTD as obtained using dtd(html,
DTD). See dtd/2.