I am unable to get this to work.
Looking at the page elements in the browser inspector window I do not see the formName property in the form-block, and thus when the form 'submit' event fires, d.formName is undefined. My form-block looks like this:
<div class="sqs-block form-block" data-block-json="{"useLightbox":false,"lightboxHandleText":"Get Info","formId":"51d4498ee4b03b50e2322d8c"}" data-block-type="9" id="block-6d99117d0a0ea3afbb33">
is there another way to get the formName from the formId?