Google updated AMP (accelerated mobile pages) documentation yesterday:

> *What*: Simplified our AMP documentation by removing outdated references to the AMP viewer, AMP Cache, and signed exchange.

> *Why*: Starting today, Google Search is updating how it connects users to AMP pages, and will now take users directly to the publisher's AMP host pages. This change simplifies and reduces maintenance efforts for publishers who are creating AMP content, as they no longer need to update the AMP cache or configure signed exchanges. AMP content will continue to rank just like any other web page.