When you import a X.509 root certificate a dialog opens asking if you wants to trust the CA and it's fingerprint is shown for comparison.
(This only happens for the first import of such a certificate, deletion and re-import does not work.)
But when you abort that action and don't mark the certificate as trusted you can then do right-click -> "Trust root certificate" and the certificate is marked as trusted immediately. No dialog is opened and no fingerprint is shown.
This is inconsistent. The right-click action should behave the same as the dialog on import.