On Thunderbird on macOS, I am trying to use a Security Device to client certificates made available by the OS for TLS authentication to IMAP servers and S/MIME signing and encryption. Under Security Devices, there is no Security Device that provides this functionality so in Security Devices I click Load and Browse... and select /Applications/Thunderbird.app/Contents/MacOS/libosclientcerts.dylib to add the appropriate security device. However, when I click okay, I get "Alert" "Unable to add module" . What am I doing wrong?

I also use libosclientcerts.dylib in Firefox just fine. Why is it not working in Thunderbird?