Regression in v25.3.0: Intl.Locale causes i18next.dir() to throw an error with non-standard language codes like "en_US" #2330
Description
💥 Regression Report
Intl.Locale breaks the use of non-standard language codes like "en_US".
Line 540 in fdc51d2
Last working version
Worked up to version: 25.2.0
Stopped working in version: 25.3.0
To Reproduce
Steps to reproduce the behavior:
i18next.dir("en_US")
// Uncaught RangeError: Incorrect locale information providedExpected behavior
A clear and concise description of what you expected to happen.
i18next.dir("en_US")
// "ltr"Your Environment
- runtime version: Chrome 138
- i18next version: 25.3.0