During a two-month period, Perl Porter developed and localized features for the thunderbird/thunderbird-l10n repository, focusing on front end development and internationalization. They migrated the FilterEditor UI to support advanced spam filtering schedules, enabling users to configure periodic filtering and improving inbox management. Using JavaScript and FTL, Perl also advanced the migration of Thunderbird’s UI components to the Fluent localization system, specifically updating Brazilian Portuguese strings for the FilterEditor and Search Widgets. Their work enhanced user experience by providing clearer action descriptions and labels, reduced localization gaps, and established a maintainable foundation for future UI and localization improvements.