How to add intro text at the top of a form

In our old web theme, you could add a message to the "Body" section when you created a new a webform. This section displayed at the top of each page of the form.

In this new theme, you can still create some introductory text at the top of your form, but it will only appear on the first page. You can do this by using the componenet type named "markup." 

If you want a message at the top of each page of your form, you can make multiple Markup components.