While I really like the Firebird 0.6 browser, there is one annoying thing that is keeping it from being my only browser: the apparent lack of SSL certificate options or management; forcing me to still load Mozilla on occasion..
When I installed my latest servers last year, I decided to protect things like IMAP, POP3, SquirrelMail and the MovableType admin pages with SSL using custom signed SSL certificates. In IE and Mozilla, this meant loading a client side certificate to gain access to those services. I haven't yet found a way to do that in Firebird, which means it can't access my MT and webmail pages. :-(

Sweet! This topic came up again on the MozillaZine forums, and there appears to be a few solutions.
http://forums.mozillazine.org/viewtopic.php?t=9987
That's weird. I have several web servers floating around CWRU that have self-signed certificates (I have an "all-SSL-all-of-the-time" policy with web application servers). When I first visited them with Firebird, I was told that the certificate did not come from a trusted 3rd party; then, I was given the option to permanently install it. I did, and I have not been bothered with certificate warnings since (from those servers).
I think there's a difference there. Self-signed server SSL certs are ok, but the interface to import self-sign ed client-side certificates was missing.
Actually Firebird does have a complete certificate manager, but it ain't obvious. Enter the following URL :
chrome://pippki/content/certManager.xul
I can't imagine why you couldn't figure it out :-)
-- Max