This behavior changed in 10.12 for applications linked against that SDK or
later. It’s listed in the “Behavioral changes” section of the Core Data release
notes for that year:
https://developer.apple.com/library/archive/releasenotes/General/WhatNewCoreData2016/ReleaseNotes.html#//apple_ref/doc/
NSButton is interesting in that it separates out the state (e.g.
`isHighlighted` and `state`) from the presentation of that state. The state
manipulation behavior is totally uniform, i.e. the `state` property always
toggles between Off and On when any button is clicked. Most buttons aren't
conf
