If you want to add social feeds from an external provider to the petition content you need to create a basic subpage of your petition page in order to add the embed code which provides your favorite platform.
1 - Edit your petition pages, go to Subpages and then Click on a New subpage, name it Social Feeds, make sure its slug is social_feeds and choose Basic as Type of page.
The Excerpt field would look something like this:
The social feed will be shown below the petition content and the result would be something like this:
Best Practices for Feeds:
Use the social network feeds to add updates about your campaign. Have you reached a ‘milestone’ number of signatures? Has someone ‘well-known’ added their support for the campaign? Did you deliver the petition? Have you reached a victory or partial victory? Is there a media-article about your campaign topic? Sharing this type of information will keep your audience interested in the campaign and enable them to understand how their action is having an impact.