The subscription forms acquired multiple new perks and features. One of them is a double opt-in possibility.
The double opt-in term refers to a secondary email verification process, usually by verifying the email address via the confirmation email. The method prevents fake emails from being added to the mailing list and keeps your list clean and valid.
How does it work?
When the double opt-in feature is enabled, all new subscribers that filled the form will receive a validation email with a confirmation button. Recipients who successfully verified their emails by clicking the confirmation button will be transferred to the mailing list.
Here how the default email address confirmation email looks in the inbox: