No luck. I changed default locale from fi to en_US by commenting DISCOURSE_DEFAULT_LOCALE: fi and changing it from settings, and that didn’t help either. Safe mode gave same.
I have this in web_only.yml and data.yml:
LANG: fi_FI.UTF-8
LANGUAGE: fi_FI.UTF-8
I tried to change those to en_US.UTF-i in both ymls, but that crashed rebuilds.
Anyway — I would say it isn’t matter of locales either 
Ill start digging personas, but those should be default ones, I havent edited any of those.
After all — this isn’t bigger issue.