Unfortunately that plug-in totally unusable when the heading more then a few words long as it make a complete mess of things. If the headers are one or two lines long (for example a FAQ page) then the Disco TOC plug-in makes a complete mess of the page which is why I had raised this request for an inline TOC (which this one provides) and is perfect for such pages
With the amount of genius/talent amongst the teams who build discourse it shouldn’t be that hard to include this amazing feature as an alternative to DiscoTOC to give it a much wider range of use.