Anchor tags missing from library pages

[pzich]

Description of problem

Pages in the registry (e.g. https://registry.platformio.org/libraries/esphome/ESPAsyncWebServer-esphome) have a Table of contents section for their readme, which feature links to other sections (e.g. <a href="#important-things-to-remember">), however there don't seem to be corresponding elements with id tags, so the section is not focused / scrolled to.

document.getElementById('important-things-to-remember')
null

Steps to Reproduce

1. Visit https://registry.platformio.org/libraries/esphome/ESPAsyncWebServer-esphome
2. Click one of the links in the Table of contents

Actual Results

The hash is added to the URL, but otherwise nothing seems to happen

Expected Results

That section of the page is focused / scrolled to.