locales/keyboard layout w/ persistence?

Briefly describe your issue below:
Managed to get Parrot OS Home running live from USB stick and installed persistent volume an same stick (as described on parrotsec.org).
Now I’ve been trying to switch locales to de_DE, including keyboard layout. I finally managed to have it switched during boot (e.g. for entering the harddrive password) but as soon as Parrot has loaded and I try to login (I altered passwords and created a new user) the keyboard layout has fallen back to en_US (I guess) again.
I suppose, I have to change settings for locales on the persistence partition? How do I do this?

What version of Parrot are you running? (include version (e.g. 4.6), edition(e.g. Home//KDE/OVA, etc.), and architecture (currently we only support amd64)

parrot os 4.6 home amd64

What method did you use to install Parrot? (Debian Standard / Debian GTK / parrot-experimental)

live usb with persistence

Configured to multiboot with other systems? (yes / no)
no

If there are any similar issues or solutions, link to them below:

If there are any error messages or relevant logs, post them below: