How to make the 'slim' ISO localized in your own language

Notes:
This slim ISO intentionally is in English/American language only. Therefore, the need to localize it into one’s own language for those who prefer it arises.
The procedure covers Italian but can be applied to other languages as well.

Let’s start with the ISO in live mode and proceed with the installation.
Calamares already has language support by itself so it is preferable to start it in the language of our choice.

Let’s install our locales-xx

We verify and set the language at the system level

Reboot

We set the desktop language in systemsettings (which as you can see is still all in English)

Let’s edit these files so to so

We type the command to update the home directories

We check that Locations are correct

These directories are now useless and can be trashed:

Enjoy!

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