I use an addon called Maskme which fills in fake email addresses tied to the real email. When one wants to stop the resultant spam, all he has to do is to block the email. Mozilla recommends another program that is a password program and not what I use and it doesn't mask the emails. What happened? A good little add on which I used a lot. If it can't be reinstated, I will have to finally go back to another browser, reluctantly, because that is one of the programs I use a lot, as well as one that uses activeX (which only works on Explorer). Seems like Mozilla is slowly reducing my choices!