Unfortunately it is not the Highlighters job. The highlighter is doing the basic parsing. Though the line is not 100% clear in this case. But the Markup is match better suited.The Paint class paints the text token by token. It pulls them from the HL but they have a long way.
pardon the intrusion, you meant something similar like SynUniHighlighter or SynFacilSyn ? (first seems hard to find, here perhaps ?)