'Interpolation failed: Non-string return value: undefined' with FI-locale

[Aapo Rantalainen]

Happens only with: locale=fi_FI.UTF-8
libkf5i18n-data (version 5.18.0-0ubuntu1) contains file /usr/share/locale/fi/LC_SCRIPTS/ki18n5/ki18n5.js which seems to have something wrong. When starting several KDE-applications (e.g. kcalc, kate, gwenview) there were errors:

KTranscript: Loaded property map: /usr/share/locale/fi/LC_SCRIPTS/ki18n5/general.pmapc
KTranscript: Loaded module: /usr/share/locale/fi/LC_SCRIPTS/ki18n5/ki18n5.js
"Interpolation {$[gen %1]} in {$[gen %1] &asetukset...} failed: Non-string return value: undefined"
"Interpolation {$[gen %1]} in {$[gen %1] käyttö&ohj...} failed: Non-string return value: undefined"
"Interpolation {$[elat %1]} in {&Tietoa $[yleisnimi_...} failed: Non-string return value: undefined"

KDE Frameworks 5.18.0
Qt 5.5.1
Ubuntu 16.04
kate 4:15.12.3-0ubuntu2
kcalc 4:15.12.3-0ubuntu1
gwenview 4:15.12.3-0ubuntu1

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.