Blocking certain domains in Firefox

[Praetorius]

I have a handful of domain names that always pop-up in SpyBot S&D as Firefox cookies. They're always the same domains. Under Firefox's Security>Exceptions, I can only add site to allow, not block. Is there a way to block Firefox from saving cookies from these sites?

 

[keenan]

Options/Privacy - click Exceptions and add the domains there. You may need to switch to 'Use custom settings' in the drop down at the top to expose the options.