Only first title in sidebar

[HaiyiMei]

Describe the bug

context When I add .. toctree:: in index.rst like this:

Welcome to test's documentation!
================================

.. toctree::
   :maxdepth: 2
   :caption: Contents:

   tmp.md

The content of tmp.md is:

# head1

# head2

## head2.1

expectation After build the docs, I expected the sidebar (or so-called navbar) to have every first-level head of .md file, which is head1 and head2.

bug But instead, I got only the first title in sidebar like this:

Reproduce the bug

All files are compressed into test.zip: test.zip

The main files of this zip are as follows:

index.rst:

.. test documentation master file, created by
   sphinx-quickstart on Tue Sep 20 11:08:35 2022.
   You can adapt this file completely to your liking, but it should at least
   contain the root `toctree` directive.

Welcome to test's documentation!
================================

.. toctree::
   :maxdepth: 2
   :caption: Contents:

   tmp.md



Indices and tables
==================

* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`

tmp.md

# head1

# head2

## head2.1

conf.py

# Configuration file for the Sphinx documentation builder.
#
# For the full list of built-in configuration values, see the documentation:
# https://www.sphinx-doc.org/en/master/usage/configuration.html

# -- Project information -----------------------------------------------------
# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information

project = 'test'
copyright = '2022, mei'
author = 'mei'

# -- General configuration ---------------------------------------------------
# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration

extensions = [
    # 'myst_parser',
    'recommonmark',
    'sphinx.ext.viewcode',
    'sphinx.ext.autodoc',
    'sphinx.ext.napoleon',
    'sphinx.ext.intersphinx', 
    'sphinx.ext.autosectionlabel',
]

templates_path = ['_templates']
exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']



# -- Options for HTML output -------------------------------------------------
# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output

html_theme = 'sphinx_book_theme'
html_static_path = ['_static']

List your environment

No response

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[flying-sheep]

I don’t see any captions in the sidebar currently, what happened?

[sgbaird]

I think this is intentional, but I'm finding myself wanting to be able to do the same, where there are multiple H1 headings, and having those show up on the primary sidebar. xref: https://github.com/executablebooks/sphinx-book-theme/issues/337