Butterfly keyboard

The "butterfly" keyboard was a mechanism that was introduced as a feature of the Retina MacBook in 2015, the MacBook Pro in 2016, and the MacBook Air in 2018. However, it was prone to problems and was replaced by the Magic Keyboard, starting in November 2019, and completely phased out by May 2020.

Lawsuit
In July 2022, Apple agreed to settle a lawsuit from dissatisfied customers for a total of up to 50 million. Individual users can get reimbursed from $50 to $395, depending on the level of issues encountered.