Files located at "assets/x/lang" (where x is the modid youre looking to translate), which are the localization files, are AUTO GENERATED by an external tool in the repo ("minecraft/tools/LanguageMerger") This means that any changes done to the files in "assets/x/lang" WILL BE OVERWRITTEN the next time the tool is ran! If you wish to properly write localization for an already supported/translated mod: 1. Go to the [Tools-Modern] repo 2. Go to the folder of your mod of choice. 3. Open the Localization folder for your language, these are the actual locales supported by the mod (ie: en_us) * If youre looking to add a new language, create a new folder with your chosen locale 4. Edit, or add a new JSON file with your language values. [Tools-Modern]: https://github.com/TerraFirmaGreg-Team/Tools-Modern