Improvement
You can now customize the behavior of our web-based online forms by adding some query parameters to the URL. You can use query params to set default data for fields, set some "metadata" on the submission, or hide fields from the form. This can be useful when you want to build a quick integration to collect information from your users and fill out PDFs.
Note: These query params will not work for embedded forms on your own website, but you can achieve the same result by using the JavaScript API.
See the Web Forms - Query Params documentation for more information.