header label in doxygen markdown page makes header title disappear

After some investigation, I have decided this appears to be a bug, but only because it is slightly counter-intuitive.

Consider the following:

The Main Section {#the_main_section}
================

Subsection One {#first}
--------------

Something highly interesting...

The document starts with a level 1 header (as described here) and so Doxygen parses "The Main Section" as the name and title of the page. The header and the label {#the_main_section} appear to be disregarded once the header has been converted into a page name.

The processing then moves on to the rest of the document and When it reaches "Subsection One", it believes that there is no parent "Section" for the "subsection" (as the "Section" was converted to a page name) and this is where it chokes.

More specifically, it discards the subsection (header) as it believes there is no parent "section". All other text remains, but is treated as part of the "page" (with no section parent).

The "fix" is to add another "level 1 header" after the initial "level 1 header" e.g.

My Great Documentation (Which Becomes the Page Name)
====================================================

The First Section
=================

Q. What? I already created a level 1 heading?
A. Yup, but that was converted to a page name/title and discarded, so now
   we have to create another level 1 heading for my first section. Don't
   be fooled into thinking that the opening heading in this document is
   still treated as an opening heading by Doxygen - it's not!

Same issue in the version 1.8.9.1. You can avoid it by using # tags instead of --- .

For example:

[TOC]

Page Title {#pageTitle}
==========
Lorem ipsum dolor sit amet

# section 1 {#section1}
Lorem ipsum dolor sit amet

## Section 1.1 {#section1-1}
Lorem ipsum dolor sit amet

# section 2 {#section2}
Lorem ipsum dolor sit amet

# section 3 {#section3}
Lorem ipsum dolor sit amet

## section 3.1 {#section3-1}
Lorem ipsum dolor sit amet

# section 4 {#section4}
Lorem ipsum dolor sit amet

will work. You can even put the [TOC] tag below the page Title definition to remove it from the table of content.