How do I include subsections in the HTML contents page when they don't have page breaks?

I’m using scrivener 3 for the mac and compiling to the mobi format. In scrivener 3 on the mac I see that chapter subsections show up in the HTML contents page of kindle desktop app only when those subsections have a page break in them. Here is the problem. If I add the page breaks, those subsections do show up, but this causes each subsection to be on a separate page. I want the subsections to flow continuously for a given chapter. This means I have to choose a layout for the subsections that does not include a page break, but if I do that then the HTML contents page will not show the subsections. How can I solve this problem so that the subsections flow continuously in each chapter but at the same time they show up in the HTML contents page? Thanks.

You can create a custom ToC.

See section 22 of the manual.

Slàinte mhòr.

If I create a custom TOC, will it also convert the custom TOC to a matching “software TOC”?