The about and mentions markups are Houses of webpage schema which explicitly tell search engines like Google and Bing what subject areas a page is mostly about and what other subject areas are merely getting outlined or referred to. Posted Oct 27, 2018 (edited) Hello, Greetings in the working day. https://explorebookmarks.com/story19335282/the-ultimate-guide-to-json-schema-is-not-supporting-please-check-your-json