In the past, whenever I signed up to some web app with Facebook, I got the option to give them a custom email address instead of revealing my Facebook email address.
It now seems to be gone:
There used to be a dropdown allowing me to select a "secret" address. Is there really no longer a way to sign up with Facebook without giving them my Facebook address?
I use a custom address for every website so that I know who leaked it to spammers and have a trivial way to permanently block it; that's why I'd rather not reveal my Facebook email address.
Best Answer
Unfortunately, this is apparently an intentional change in the new auth dialog, which is now in the process of being rolled out to all users and all applications. You may want to avoid adding any apps that require this information.