libxml-parse-html-region
libxml-parse-html-region is a built-in function in `C source code
'.
(libxml-parse-html-region START END &optional BASE-URL DISCARD-COMMENTS)
Parse the region as an HTML document and return the parse tree.
If BASE-URL is non-nil, it is used to expand relative URLs.
If DISCARD-COMMENTS is non-nil, all HTML comments are discarded.