Go to System Preferences -> Security and Privacy -> Firewall.If you prefer to set up an automator script to enable/disable the firewall to block mail.appįirst of all set the firewall to block Mail.app: I don't believe Radio Silence has a shortcut but it's really easy to set up & use (literraly launch Radio Silence, drag Mail.app into it and toggle on/off button when needed). You could also use another app (like Radio Silence) to only block mail.app and keep your firewall running (and I'd personnaly go with that solution). You can define your firewall to block mail.app when activated, then toggling it on/off when needed.
