Hi weqrkj, Currently there is not a built in feature to Firefox for Android that shows the full security certificate of a website you are visiting.

There is an add on called the Client Certificate Manager available in Android that may be useful however.

Thanks, but the add-on doesn't solve the problem, because it does not list the (unverified) certificates that prompted adding an exception. When I go to a site that has an unverified certificate, I should be able to manually check the certificate. Right now, I can add an exception, but I have no way of knowing if that is a good idea. Displaying the details or just the fingerprint would be very sensible; otherwise the user could be accepting any arbitrary certificate, say from a woman in the middle.