Thunderbird Community Forum

Every time I launch Thunderbird Beta 151.0b1 on Arch Linux, I immediately get a notification saying "The certificate for imap.gmail.com does not come from a trusted source." If I click through to the exception dialog, it shows "No Information Available / Unable to obtain identification status for this site" — it can't even fetch the certificate to show me what's wrong with it. The error only appears on launch and doesn't come back. Mail sends and receives fine.

From the terminal, openssl connects to imap.gmail.com:993 without any issue (Verify return code: 0, TLS 1.3, X25519MLKEM768). No antivirus, no VPN, no TLS-intercepting software. NSS 3.123.

Has anyone else seen this? Is this a known Beta issue?

Dear all,

When receiving signed AND encrypted mails from an Outlook-account I get the exclamation sign for the signature.

The message is (German) : "Digitale Signatur ist ungültig Diese Nachricht enthält eine digitale Signatur, die aber ungültig ist. Die Nachricht wurde mit einer Verschlüsselungsstärke signiert, die von dieser Version Ihrer Software nicht unterstützt wird. Signiert von...."

I already did all standard checks (trusted, new hash algorithm and so on),

Now I would like to know the EXACT reason why Thunderbird is not accepting the digital signature. How can I accomplish this?

THX in advance and best regards!

2026-04-25 SAT 14:45 BST I have boujht a DigiCert S/MIME Class 1 certificate from thesslstore, but I have not yet got it. They sent me 3 .crt files, but I have not understood how to use them. I hope someone can explain the problem and/or suggest what I can do about it please ? I do not remember having this sort of problem in previous years.