This came up when firing up Thunderbird to check email. It's the splash screen. It disappeared later (perhaps when you checked). The Cert definitely expired, I

This came up when firing up Thunderbird to check email. It's the splash screen. It disappeared later (perhaps when you checked). The Cert definitely expired, I have a screen grab of it showing the expiration date as 12/7/15, 7:00am. (At the point I checked it was 12/7/15, 9:51 AM.