Running check for installed modules returns XML Sitemap as unchecked (not installed/enabled)

XML Sitemap is installed and functioning correctly however, the module check does not detect it even though I can view it at domain.com/sitemap.xml

This is not a big deal, and I just ticked the checkbox myself, however I wanted to report it and to double check that this was known behavior and not an error in my XML Sitemap installation.

Thanks :)