Thanks for your report. thousands_sep for nl_NL was changed to '.' in 2019, so it's correct as from Ubuntu 20.04.
https://sourceware.org/git/?p=glibc.git;a=commit;h=fefa2179 ** Changed in: glibc (Ubuntu) Status: New => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1961342 Title: nl_NL locale has wrong 'thousand separator' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1961342/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs