balsa displays "Check cryptographic signature" button on encrypted-only (unsigned) messages
An encrypted message that has no signature should not display the "check cryptographic signature" button.
I'm reviewing the protected headers test vectors which includes some messages that have encryption but no signatures. they typically look like this:
Balsa should not show the red signature ("seal") icon if there is no signature, not even in a button with a "reload" icon on top of it.
This is a user interface issue -- not an issue about technical correctness. That is, Balsa never includes a green (sig from known-valid cert) or yellow (sig from unknown cert) lock icon around the image, regardless of whether the button is clicked. But the presence of the button itself is likely to be confusing.