> For someone without disk encryption (many people, maybe most?), I would say they should really use FDE. An attacker with that level of control can do a lot -

> For someone without disk encryption (many people, maybe most?), I would say they should really use FDE. An attacker with that level of control can do a lot - FDE is designed for this type of attacker. But yes, that is one attacker that this would protect against. > With remote compromise of the system it is presumably possible to access the key if the browser is running via debuggers, it is at least a bit more work. No need for debuggers, though that would certainly be one way to do it. This is not hard at all for an attacker, we see attackers hijacking processes all the time. Forcing the attacker to do 'a little more work' is not really the best place to spend time. Firefox's threat is, in my opinion, malicious web pages, malicious extensions, or malicious use of/ abuse of their services etc (can't even imagine what abuse they see for their recent file sharing system). These probably take a significant amount of time and resources - these are the attackers they are probably dealing most days, if I had to guess. An attacker with unlimited offline access to an unencrypted hard drive seems pretty out of scope and better solved by the OS (I believe modern Windows and OSX systems actually FDE by default now). An attacker with full execution on the system also seems out of scope. They could probably fix this master password thing pretty easily, it sounds simple enough and they might just because it's been called out, but my expectation is that this would probably not be a high priority otherwise. I would also be concerned about users making the assumption that if they use a master password that they are safer from attackers - that it 'raises the bar', when it is unlikely to meaningfully for almost any attacker. A false sense of security is not a good thing. I'm not a browser developer so I could be totally off and this could all be stuff they're super concerned about.