https://wccftech.com/apple-confirms-2018-macbook-pro-membrane-keyboard/

If you followed our teardown report of the 13-inch 2018 MacBook Pro, you would have noticed that the teardown experts managed to find a membrane on the keyboard, and there is actually a reason for this.

MacRumors recently got its hand on an internal document circulated to Apple Authorized Service Providers. Details of the document come from a reliable source and state that Apple has confirmed that the third-generation keyboard on 2018 MacBook Pro models features a membrane which prevents debris from creeping into the butterfly mechanism and crippling the lifespan in the end.