As Joe mentioned already, he's done an excellent job in creating one board to host all our Mafia private "quicktopic" chats. While the game is active, the Mafia/Observer chats will only be visible to the players who take part in them. Once the game is over, they will be visible to everyone.
Joe has done a really great job in making the whole process very smooth and documented the instructions really well. Please give a round of applause to Joe.
Strictly speaking, you'll only need an account if you get a role with access to private chat. However, to make things quicker, it might be a good idea to sign up now already. A lot of you are already there.
Please be aware though, that the admin (that's me for the moment, later it will be passed to whoever is hosting the next game), will know the email address you signed up with, so if you want to keep that secret use a (semi-) disposable one. Note though, that if you lose your password, you will need your email to recover it. So perhaps the best idea is to use a junk email; I have one that I use to sign up to all temporary accounts. https://whyquicktopicwhy.proboards.com