Enhanced 404 Pages was a JavaScript library that added suggested URLs and a search box to a website's 404 Not Found page. Launched August 19, 2008; shut down May 13, 2020 — it lived 11 years. One of 25 Google products killed in 2020. https://webmasters.googleblog.com/2008/08/make-your-404-pages-more-useful.html Data: Killed by Google (killedbygoogle.com, MIT).