This page provides links to the "Thunderbird X for developers" articles for each Thunderbird release. These notes let you see what features were added and bugs eliminated in each version of Thunderbird. Thunderbird 63 for developersThunderbird 60 for developersThunderbird 24 for developersThunderbird 7 for developersThunderbird 6 for developersThunderbird 5 for developersThunderbird 3.1 for developersThunderbird 3 for developers See also Firefox developer release notes