[Mark Daniel]

Again, exact same happening here. What I've found fixes it:

1. Log out of ZWC.
2. Quit Firefox (not just close the window), and save your session (optional).
3. Relaunch, and sign back in to ZWC.

Now, I've noticed that if I'm prompted for my master Firefox password, it works perfectly (I see my sig). If not, then chances are I'll get the plaintext version.

(I have not checked to see what happens if I disable my master password; the problem always goes away when I'm prompted for the master pass, whether or not I've just started Firefox.)

::shrug::