Interface translations override config translations on update

I think this should be re-opened. A number of people in the referenced ticket are still experiencing the issue described even after the fix. It is happening to me in the following scenario on Drupal 10.3

* I have some country names translated in locale E.g. United States = アメリカ in Japanese.
* We display country names in a language selector. That information is stored in simple config.
* Feedback from client was that country names should be displayed in their own language in the language selector. Translations should still exist in other contexts though.
* Put United States for the translation of United States in the Japanese config for the language selector. You could even delete the whole config file.
* Re-import locale like so: drush locale:import --type customized --override customized ja /app/translations/ja.po
* Export your config. You will notice that the config has been overridden with アメリカ

Drupal 9 is EOL. Changes are made on on 11.x (our main development branch) first, and are then back ported as needed according to the Core change policies → .

It would help to have one issue for the discussion. Can you comment on the other issue that this is open? And update the Issue summary with the most recent steps to reproduce. Thanks

I can confirm this is still happening, as reported by @achap and it's a critical issue for multilanguage sites.
Technically it might make sense to postpone this on ✨ Configuration langcode is forced to site default language Needs work but that would also mean that issue should be seen as a critical fix.