You can find the updated article here
Display Page allows you to display a message on a web page to a user who clicked a special link.
See how to create an External Link here
Display Page can only be used in an External Link trigger flow. Select Display Page from the sidebar.
In the text area, enter the content you wish to display on the page. You're free to use other actions and collectors in this flow but is recommended that they are put above this action block.
For Example:
In this example, we collect all the data from a purchase and create a Detail HTML table to be displayed on page.
When the link is clicked on, the results of our external link flow are shown here.