The OpenType script tag registry has been updated to sync with
Unicode 11. The registry never got updated for Unicode 10 (an oversight), so
additions include scripts added in Unicode 10 and Unicode 11 — 11 additions in
total. All of the script tags match the script IDs of ISO 15924 (modulo case
conventions).
https://docs.microsoft.com/en-us/typography/opentype/spec/scripttags