<http://schema.org/description>
"There has always been rumors that Google used the data they get from the Google Toolbar to discover new content, outside of the normal crawling or sitemaps method.  But those rumors have been debunked"^^<http://www.w3.org/2001/XMLSchema#string>
<https://www.seroundtable.com/google-toolbar-indexing-12894.html>