> §5.5.3 - As I understand it, this creates an inescapable obligation on
> user agents to store certificate history. Aside from the challenge
> that no major browser currently does this (as far as I know), this
> creates privacy and implementation concerns around data retention. We
> don't say how long this information must be kept, but we say the
> browser MUST treat it as a change of security level, which does not
> seem to leave open the possibility of not storing it.
I read it as remembering those two states for sites visited (strongly TLS
protected and AA cert). Which isn't exactly the same thing, is it?