As we can see in the following screen shot (choose “book” as the style), subparagraph is not showing “correctly” in the TOC. I don’t understand why toc-5 is defined as it is now, is it a bug or feature?
To me it seems a bug. I would submit it to the bug tracker, and in the meantime you could redefine it following the pattern of the
toc-4 definitions (I did not test this).
Yes that can fix it. I’m just not sure if there is other thinking behind this and I’m not aware of