Digital signature using a smartcard (the beligian eID) and S/MIME works with Thunderbird on Ubuntu 16.04 LTS On Unbutu 18.04 it doesn't (same version, identically configured). I precise that all other functionalities of my eID work work on this platform (Be government web sites strong authentication, documents digital signature, ...). S/MIME email encryption/decryption works as well using Thunderbird. Only email digital signature is not working. Can you help? Should I apply for help with mozilla or ubuntu support? Thanks for your answer.