The reCAPTCHA element is always required, meaning it must be filled out by the user before the form can be submitted

Required error message

reCAPTCHA → Settings → Optional

Change the required error message by entering text into the Error message if required field.

Required indicator text

Settings → Style → Labels

Change the text indicating the element is required. By default this is (required), but you may want to make it an asterisk * for example.

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