Thunderbird Release Notes
Security vulnerabilities fixed in Thunderbird 52.9
追記
Thunderbird locked up by latest update - Kaspersky lab Forum
問題ないけどな
さらに追記
https://forum.kaspersky.com/index.php?/topic/397146-%D0%B7%D0%B0%D0%B2%D0%B8%D1%81%D0%B0%D0%B5%D1%82-thunderbird-%D0%BD%D0%B0-%D0%B2%D1%85%D0%BE%D0%B4%D1%8F%D1%89%D0%B8%D1%85-%D0%BF%D0%BE%D1%81%D0%BB%D0%B5-%D0%BF%D0%BE%D0%BB%D1%83%D0%B4%D0%B5%D0%BD%D0%BD%D0%BE%D0%B3%D0%BE-%D0%BE%D0%B1%D0%BD%D0%BE%D0%B2%D0%BB%D0%B5%D0%BD%D0%B8%D1%8F/&tab=comments#comment-2811596
既に終わってた (´・ω・`)