From ADF Docs
Comments Box Custom Element for allowing users to post comments on your site's pages and share those comments, along with a link to the page, with their friends on Facebook.
To set up a demo of the Activity Feed custom element, follow these steps:
- Create a new page and place the Comments Box element on the page.
- Click the 'New Data' button.
- Edit the custom element data to your liking (or just leave the defaults) and click Save.
- Submit the changes to the page.