SUMMARY STEPS TO REPRODUCE 1. access System Settings -> Regional Settings -> Formats -> Region settings on an installed system with KDE Plasma desktop 2. check settings available for Finland OBSERVED RESULT Listed are sms_FI, sv_FI and en_FI EXPECTED RESULT Listed should be fi_FI and sv_FI. I doubt there even is en_FI nor sms_FI locale. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Observed on Arch Linux and Fedora 31 at least (available in About System) KDE Plasma Version: 5.18.4 KDE Frameworks Version: 5.69 Qt Version: 5.14.2 ADDITIONAL INFORMATION
Scroll down to "Suomi (fi_FI)". The actual list of locales is fetched from the OS, so if you believe it is wrong, please report it to the bug tracker of your distribution.
Okay, that's fair. I just didn't know how these are determined. Thanks.