Kerim contributed to the thunderbird/thunderbird-l10n repository by migrating message retention strings to the Fluent localization format, focusing on enhancing internationalization and localization support. Using FTL and leveraging expertise in software development, Kerim restructured existing strings to improve coverage and consistency across multiple locales. This work addressed Bug 1744107 as part of a broader Fluent migration effort, ensuring that message retention features are more accessible and maintainable for global users. The project demonstrated a solid understanding of localization workflows and the technical requirements of Fluent, resulting in a more robust and user-friendly experience for Thunderbird’s diverse user base.