If others managed to render the <sup> tag, with the above Goldmark configuration, as discussed in the topic you linked to above and you cannot get it working, then you will have to share your project for us to see what is going on.
If others managed to render the <sup> tag, with the above Goldmark configuration, as discussed in the topic you linked to above and you cannot get it working, then you will have to share your project for us to see what is going on.