This document is outdated.
https://developer.apple.com/library/archive/technotes/tn2056/_index.html
I am not able to find the latest version of this keyboard.
Also, does mac OS and support LDML layout?
https://unicode.org/reports/tr35/tr35-keyboards.html#Introduction
http://www.unicode.org/review/pri367/pri367-Unicode-LDML-Keyboard-Enhancements.pdf
