ConstA locale identifier in the form of "{language}-{region}"
Messages in the Fluent syntax
Optionaloptions: { direction?: "ltr" | "rtl" }
Optionaldirection?: "ltr" | "rtl"The text direction of a new locale. It's ignored if the locale already exists.
Adds Fluent messages for a locale, such as messages for a custom keyword or a translation for a locale that isn't included. A message with the same id as an existing message replaces it. Messages that aren't translated for a locale fall back to en-US.
Messages for keywords use the ids
{keyword}-messagefor errors and{keyword}-success-messageand{keyword}-negated-messagefor describing what a keyword requires.