We have been using ACF Content Analysis for Yoast SEO to help with the SEO on our websites.
When we use the keyword density checker, it doesn't highlight the correct content and it throws issues and spits out Html code into the visual editor.

Keyword: Kyphiosis
Techincal information:
- Wordpress Version : 6.7.1
- ACF Content Analysis for Yoast SEO version: 3.1
- Yoast SEO Version: 24.4
- Yoast SEO Pro Version: 24.4