Editing Apple butterfly mechanism (section)

==History==
===1st-gen===
Apple is using this mechanism along with a stainless-steel [[Metal dome|dome switch]] on the MacBook (Retina, 12-inch, Early 2015).<ref name="Apple-MB-PR" />

===2nd-gen===
The 2016 MacBook Pro (13 and 15-inch, with or without [[touch bar]]) come with an updated mechanism.<ref name="arsapple16liveblog" />
The keys are taller at the edges making them easier to find by feel. The [[metal dome]] is heftier and mounted to the keycap.<ref name="ifixitmbp16" /> 

===3rd-gen (2018)===
The 2018 MacBook Pro keyboard got a protective membrane over the dome switch. According to Apple, it was added to reduce noise but it has been speculated that the real reason was to avoid failure in the "butterfly" mechanism from exposure to dust.<ref name="ifixitblog18" />

===4th-gen (2019)===
When announcing the 2019 MacBook Pro, Apple told that the keyboard was slightly changed so as to be less susceptible to problems such as keys becoming unresponsive or [[chattering]].<ref name="macworld2019mbkb"/>
iFixit showed that the protective membrane got changed from a poly-acetylene to a thicker layer of polyamide (nylon).<ref name="ifixitvideo19" />

===Replacement (2019)===
It got discontinued for new MacBook models in late 2019. It was replaced with more traditional scissor switches with rubber domes, called [[Apple Magic_Keyboard#Portable|Magic Keyboard]] like the keyboards for contemporary desktop Macintoshes.