Submit the newsletter block. An empty or wrong email address is stopped in the browser; a good one is sent to the site's mailing list storage.
Examples
When I submit the newsletter form
When we submit the newsletter form
And I submit the newsletter form
When submit the newsletter form
And we submit the newsletter form
Pattern
When(/^(I |we )*submit the newsletter form$/, …)
Part of @webship-js/squarespace-steps (github.com/webship/squarespace-steps), a step pack for Webship-js 2.0.x.