Useful Resources for Data on Characters, Languages, and Keyboards

The Character Usage Lookup Page will let you find info regarding the characaters used by any particular langauge, or the languages which use any particular character.

The Unicode CLDR Keyboards Database will let you find which keyboard layouts produce which characters for a variety of computer platforms.

MacOS 10.13 High Sierra: New Language Features

So far I have found the following:

+One new system localization -- Hindi

+A nastaliq Arabic font for those who want to use this in Urdu or elsewhere

+New bilingual English dictionaries for Russian and Portuguese

+Caps Lock language switching now works for Greek, Cyrillic, and Armenian (not the case in Sierra)

I don't see any new spellcheckers or new language coverage via keyboards -- Lao and Amharic are still missing, even though Apple does provide fonts for these.

A language setting in the Format preferences, removed in Sierra, is still missing.

MacOS Siri cannot do translation like the iOS version can.

If readers find others, please comment.