The Thunderbird team has revealed a new logo, designed by Jon Hicks who created the original Firefox and Thunderbird logos. The redesign comes after years of being viewed as stagnant, as Thunderbird sees a resurgence in popularity. The software is evolving into something more modern, while retaining its powerful customization capabilities. The new logo represents a fresh start for the project and will be integrated into Thunderbird 115, Supernova, this summer. The team hopes users will let the new design breathe and sink in before providing feedback. The project is changing in big, positive ways and the new logo highlights this revitalization.
https://blog.thunderbird.net/2023/05/introducing-the-brand-new-thunderbird-logo/