I am running 64 bit Thunderbird version 91.3.0 on Windows 10 64 bit. I have been testing OpenPGP Encrypted email and '''Email Certificates''', with great success. I have been trying to proceed with an email certificate, which has not been configured with a genuine internet certificate authority, but is just self signed, and generated via OpenSSL. When sending such a message, Thunderbird tries to read the contents of the email certificate and verify it. Which of course it cannot, in itself. However, it next gives me another dialogue, allowing me to set a '''Security Exception''' on that failure which will be remembered for the purposes of that inbox account. It then ignores verification for that thereafter, and keeps going. '''Where in Thunderbird go I go to view, delete, edit or add these Security Exceptions?'''