Worked on the thunderbird/thunderbird-l10n repository to enhance localization by implementing French pluralization logic for the attachment removal command, ensuring UI labels accurately reflected the number of attachments for French-speaking users. Focused on front end development and internationalization, the work involved migrating the compose localization pipeline to a PluralForm-based framework using JavaScript, which improved consistency and maintainability across locales. By unifying localization-related changes and reinforcing locale-specific user experience standards, the developer contributed a targeted feature that addressed pluralization challenges, supporting a more robust and user-friendly interface for international users without introducing new bug fixes during the period.