Not sure why Firefox recommends this extension that completely fails to work. Only blocks one site, and only after programming it twice. Terrible interface. Blocking hours very confusing. Gets the information by asking what time you want things 'unblocked' first. My advice to Ray would be eliminate the "unblocking" part. Just focus on what times people want things blocked. Very confusing when you ask "what time do you want things unblocked?" Get rid of the "generate unblocking hours automatically," if you need it, that should be behind the scenes.