During December 2024, Petri Hamalainen contributed to the thunderbird/thunderbird-android repository by updating localization for the Android legacy UI. He focused on refining translation strings using Weblate, ensuring that the user interface accurately reflected current language standards across supported locales. Petri’s work did not involve changes to application logic or bug fixes, but rather centered on maintaining and improving the quality of multilingual support. By leveraging Weblate and working with Android resource files, he helped sustain the project’s localization workflow. This effort ensured that the legacy UI remained accessible and up-to-date for international users, though technical depth was limited.