Very good, a couple of imporovements needed Noté 4 sur 5 étoiles
This extension, or something like it, is necessary for https to be usable as it was designed (makes little sense to demand https without checking certificates, and manually checking every certificate is impractical).
That said, I agree with joey2012. After using Certificate Patrol for a couple of months, the most important improvement would be to split a single "Accept" button into two, "Add" and "Replace", so that multiple certificates could be stored for a domain.
And another thing that annoys me is that the bar that appears and auto-hides at the top, sometimes multiple times per page, shifts the page up and down. So I could be clicking on a link or a button, while the bar decides to hide at the same time, and I end up clicking on the wrong button. Maybe the bar could be at the bottom, maybe there should be an option to have a button in toolbar that changes color with the warnings instead of the bar.