split the logic into two functions: one to render the echoarea and one to rendere the minibuffer (when it's active).

and a bit of foreshadowing... :)

there's a close relationship between the echoarea and the minibuffer, but let's call it echoarea for now.

This would leave the last column white if !olivetti-mode and a background color for some body lines

Don't crash when there's a certificate mismatch and after saving the cert, before choosing to persist it, the page gets redirected; also, don't repeat the "Certificate mismatch" after the first yes, if there's a redirect. Now when the user accept a certificate, is treated as temporary saved for the whole session.