code: private void initializeCategoryTranslation() {
      flatCategoriesLst.forEach(category -> {
        translationServiceProperty().addListener((observable, oldValue, newValue) -> {
          category.translate(newValue);
          // listen for i18n changes in the TranslationService for this Category
          newValue.addListener(() -> category.translate(newValue));
        });
      });
    }
docs: Sets up a binding of the TranslationService on the model, so that the Category's title gets
  translated properly according to the TranslationService used.