Linktext in "Section index" element triggers yoast warning "linking to another page"

[dieMelanie]

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• I've searched for any related issues and avoided creating a duplicate issue.

Please give us a description of what happened.

Our customer has a long page on "widget" and uses the "index section" elements to create shortcuts to special sections like "red widget" and "green widget" on the same page. The link in the section index triggers the focus key warning in the seo section of yoast. (focus keyword "widget")
We are using a base href for the site, so the anchor is given with an absolute url with the domain name.

Please describe what you expected to happen and why.

Links that point to another section of the same page should not trigger this warning.

How can we reproduce this behavior?

1. create page with focus keyword that has seveal subsections that use the focus keyword in phrase combinations
2. use element "section index" to create al jump navigation
3. check yoast warnings

Screenshots

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Logs

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Additional context

I am not sure if it is a major problem, but it would be nice to restrict the warning to actual external links.

Technical info

• TYPO3 version: 8.7.22
• Yoast SEO version: 3.04
• Relevant extensions in case of a bug: