This module blocks outgoing emails after reading the setting of a configuration form. Its extremely useful in development environments where outgoing emails will cause problems if they are not blocked. For example, the dev environment with a cron job sending emails with invoices to existing customers would be problematic as they will receive mails from prod as well.

The module uses the hook_mail_alter supplied by Drupal 8 to block the emails. This module is intentionally kept simple and with a small footprint.