[Forminator Pro] reCAPTCHA issue

In each form, i added reCAPTCHA and set it invisible.
If users use firefox, reCAPTCHA changes as an annoying image verification.
I know that if users login their gmail account, image verification disappear. But it is not user-friendly to ask all my users to login their gmail account before use the form of my site.
In admin console of google recaptcha -->Security Preference, i set: Easiest for users, but still no luck.
Is there any way to make reCAPTCHA really invisible or only a simple click on the checkbox to verify?