[Plugin: WordPress SEO by Yoast] No Tags in sitemap

Every now and then I make the same question in the hope the developer will eventually grace me with a much appreciated answer.

In EXCLUDE TAXONOMIES I have nothing checked, yet my site sitemap does NOT include TAGS. The XML Sitemap Index files only contains 3 sitemaps (post, page, category).

Thanks!

https://www.ads-software.com/extend/plugins/wordpress-seo/