Base translatable strings are placed under `i18n/en/czkawka_gui.ftl` file.
`czkawka_core.ftl` is just a symlink which point to file from above(I had problems with splitting string into two separate crates)
Since such strings are heavily integrated into build system, so to check status of translation it is required to recompile Czkawka.
`czkawka_gui.ftl` file contains lines in this format:
`id_of_message` = `translated_string`
e.g.
```
upper_manual_add_included_button_tooltip = Allows to add directory name to search by hand
```
to create new folder with translations, it is required to create copy of `i18n/en` folder and give it name from [ISO 639-1 code standard](https://www.loc.gov/standards/iso639-2/php/code_list.php) - e.g. pl, en, ru, fr etc.
The simplest method is to remove `en` folder and replace it with needed one.
Next Czkawka needs to be compiled and run.
### Adding new translation
Recommended way to test translation, is to add it directly to Czkawka source code.
After creating proper and well named folder and translating string inside it, to be able to be able to choose this language file it is required to modify `czkawka_gui/src/language_functions.rs` file.
`combo_box_text` must contains native and english name of language e.g. `Polski (Polish)` - English is only exception because in both versions is exactly same.