I’m currently so close to fixing my issue of passing a Webflow form input into a Pardot form input. I’m currently using a Webflow form email input, and then upon submission it opens up a modal with a Pardot form inside it.
Ok, I’ve stripped out the entire code page to get only the two elements that matters: the webflow form and the pardot form. Unfortunately, it seems the pardot form is being generated via an iframe. To my knowledge, unless you can specify a custom attribute for the email within the iframe’s markup, there is no way to inject or customize the iframe’s generated form’s field after the page has loaded.
Here is the codepen, as you see the id you’re trying to target in the javascript doesn’t refer to any id within your iframe unfortunately.