Mellisa: Where do I insert the "newsletter-popup__submit" class?

[jpbraun]

Hi,
I am using the Theme Mellisa. It contains a newsletter popup.
Where do I have to add the "newsletter-popup__submit" class?

Theme -> Newsletter -> "Remember to add a "newsletter-popup__submit" class to the submit button for the proper working of the newsletter popup."

https://getpublii.com/docs/make-newsletter-form-functional-and-visually-appealing.html
"Some Publii themes, especially Premium such as Mellisa or Cortado include a newsletter form in the popup. In order to make the [Close] and [Submit] buttons work properly just add to the second one a "newsletter-popup__submit" class."

Best regards,
Jan-Peter