I know,
there are many discussions about language packs. But I really miss the possibility to change the language of the user interface in Libre Office in German, not for me, but for my parents.
The multi-language pack of libre office has 5 MB more than the normal version.

PS: The best portable meta-software I know! Special thanks to Christophe (opendev) for your work. I wish you the best for your future.

Greetings from Berlin,
Jaro.

Hello Jaro,

The easiest way to do this is:
- close LibreOffice if it is running
- go to the folder "Apps\LibreOffice\LangPack"
- run LibreOfficeLangPack.exe
- click the menu item "options \ no confirmation" (easier if checked)
- in the header of the top list (languages), click "uninstall all"
- do the same with the bottom list (Dictionaries)
- when all items in both list are grayed, check "German" in languages and "German (Germany)" in Dictionaries.
- wait for both entries become green
- Quit "LibreOffice Language pack" and restart LibreOffice, it should start in german (sometimes you'll need to launch it twice after language changes)