There are 14 vulnerabilities has been addressed and fixed under this security updates. Some of the vulnerabilities result in a potentially exploitable crash. Mozilla Thunderbird is a free and open-source cross-platform email client, RSS and chat client developed by the Mozilla Foundation. These flaws cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but are potential risks in a browser or browser-like contexts. This Thunderbird 60 released with newly updated logo, various improvement in Calendar and attachment handling.”]
Source: https://gbhackers.com/mozilla-released-security-updates/