I regularly receive and send emails with an S/MIME signature on a ECA card (certs are authenticated via the US Government). I also use a Yubikey for MFA, those certs are authenticated by our local certificate server. Several emails per day are encrypted with the certificates on the ECA card, mostly received. I use ActiveClient as the driver for the ECA card. The last few releases of Thunderbird have been particularly problematic in that 1) if the ECA card has not been previously authenticated with a PIN, and I try to send a signed email, the Broadcom card reader does not recognize when the ECA card is inserted, although it does see the Yubikey device, 2) If the ECA has been authenticated within the 10 minute timeout period, Thunderbird will let me send a signed email; 3) after the card has timed out 2-4 times, Thunderbird no longer responds after trying to read an encrypted email even if I authenticate the ECA using ActiveClient or going to a secure website that requires the ECA card for access. Note that FireFox will let me successfully re-authenticate no matter how many times the authentication has timed out.

My current issue is that I cannot get Thunderbird to respond at all, as the last thing I tried to look at was an encrypted email. Every time I restart Thunderbird, it opens on that email and I can't seem to close the tab before it locks up, then gives me the spinning wheel... Attached is a screen shot of task manager where TB is not responding. I will try rebooting next to see if I can get a cleaner start to TB get the version number, and read a couple of emails before it locks up.