Hi David. Thanks for the reference but unfortunately I can't figure out how to apply it to my situation. That thread seems to be referring to some kind of Windows key exchange bug, but I can't see how it'd apply to Cloudberry Backup running in Linux. (Apologies if I've missed something in that thread.)

As far as I can tell, the problem I'm having seems to more to do with Cloudberry Backup simply refusing to acknowledge an updated cert from Backblaze B2, even after I've told it to trust it. It just repeatedly asks me to trust the certificate, then acts as if it hasn't noticed I clicked the Trust button whilst still appending identical copies of the new certificate to its trustedCerts.pem configuration file.