MacBook Pro document confirms 'anti-debris' keyboard redesign
 

When iFixit tore down the new MacBook Pros, it found silicone barriers protecting keyboard switches. While Apple claimed these were to make the keyboards quieter, others suspected that the membranes were a way for Apple to fix its troublesome keyboar...

https://www.engadget.com/2018/07/19/...sign-fix-leak/