Prose articles does not seem to put anything into the Article Table of Contents, even if you have header tags. The only thing that shows up, is a small empty box. I do not know if this is intended, as proses do have a different structure than other articles, so I am reporting it as a bug just in case. If proses are not intended to have a table of contents, then I feel like not even the TOC box should show up.
While editing prose article:
2nd reproduction step should say to "Put the 'articletoc' bbcode at the top". I think I accidentally put the actual bbcode when writing this out, so it kind of screwed up the list
Hey there :) Prose articles are not part of the article "content" system which is the reason that the Article ToC doesn't work for them - this is not a bug - it is a lack of a feature though - one I completely understand. A good course of action for this would be to add a feature request so we can see the community desire for this and take it from there! In order to do that head to: https://www.worldanvil.com/community/voting/