Package README some self links non-functional

[HarryLack]

Describe the bug

Some links within the READMEs of packages don't correctly navigate to other sections of the README.

This works: https://www.npmjs.com/package/flexlayout-react#dynamically-changing-the-theme
While this doesn't: https://npmx.dev/package/flexlayout-react#user-content-dynamically-changing-the-theme

Working: https://www.npmjs.com/package/ink#text
Non-working: https://main.npmx.dev/package/ink#user-content-text

Unsure if related but also noticed that some anchor contents are not being displayed:

Additional context

No response

Logs

[RYGRIT]

Thank you for your feedback. This seems to be related to #1323. I submitted a PR on this issue, but just tested a preview version and found that your problem persists. I will continue to improve this PR #1776.