Fix to check if section headers exists; small improvements, too

[tynandebold]

Description

Fixes #182

Development notes

Added a TS check for the headers. This was what was causing the failure.

Also added some other small improvements while I was in there.

QA notes

Try to preview Jo's post and ensure that it works.

Checklist

• [ ] Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• [ ] Added tests to cover my changes, where applicable

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