wbamberg/browserid-field-guide — comment on commit 65b7cab3d465d2f8a4761c43f0f98411f25dac4d
File: why_browserid.html line 83
By wbamberg:

So I think I missed something here, which is that the assertion (the email address) and the user certificate both have validity periods, and here I only mention the certificate's validity period. The assertion's validity period can be very short, but the user certificate's validity period is substantially longer, because according to my understanding, once the user cert expires, the user has to log into the identity provider to get a new one (see my comment above). But maybe I'm wrong about this..