nl_tokens: reconcile output of htmlparser2 s toString () with the original document
pl_tokens: function ignoreExtraSpaces ( <mask> ) { return string . replace ( / (\s+) / g , '\\s+' ) . replace ( / (<\\\/) / g , '<\/\\s*' ) . replace ( / (<) / g , '<\\s*' ) . replace ( / (>) / g , '\\s*>' ) ; }