37
Our Fastest, Most Beautiful Release Ever: Thunderbird 115 "Supernova" Is Here!
(blog.thunderbird.net)
Thunderbird is the leading free and open-source email, calendaring, newsfeed, and chat client with more than 20 million active monthly users across Windows, macOS, and Linux. One of Thunderbird's core principles is the use and promotion of open and decentralized standards.
This is an unofficial forum for Mozilla Thunderbird and feel free to join and discuss
The icon seems slightly smaller for me as well (Fedora KDE).
I guess it is because they want to display the mail count on the upper-right, but still, looks a bit out of place.