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toLocaleString outputs different in FF Developer

  • 2 replies
  • 2 have this problem
  • 48 views
  • Last reply by Brahma Dev

Brahma Dev
Brahma Dev

new Date(1743623960000).toLocaleString(['en-ES'])

outputs "4/2/2025, 7:59:20 PM" in normal firefox and "2/4/2025, 7:59:20 PM" in Firefox Developer. Test on MacOS and Ubuntu.

new Date(1743623960000).toLocaleString(['en-ES']) outputs "4/2/2025, 7:59:20 PM" in normal firefox and "2/4/2025, 7:59:20 PM" in Firefox Developer. Test on MacOS and Ubuntu.

Modified by Brahma Dev

All Replies (2)

TyDraniu
TyDraniu
  • Top 10 Contributor

I don't think we understand 'en-ES'. It should be 'en-US' or 'es-ES'.

Brahma Dev
Brahma Dev Question owner

Thanks. Is there some web page where such different behaviours between Firefox Developer and Firefox is maintained ?