Add some explanation of certificate storage being disabled
In Tor Browser 4.0.8 (windows) I was unable to import certificates until I changed preference security.nocertdb to false (#13366 (moved)). I tried the directions in #13353 (moved) but disabling private browsing mode didn't work to enable the certificate storage.
There is no warning that certificate storage is disabled. When you add a certificate nothing happens. Also when you view a site with an unrecognized certificate the 'Confirm Security Exception' button does nothing. Please consider making some changes to add a message box "This feature will not work with the current settings because foo. To enable this feature do bar."