Logged in users can see recommended Debates or Proposals listed with the ordering option "recommendations".
The list shows, ordered by votes descending, those elements that:
Have tags that interests the user. Being those tags the ones on the proposals that the user follows.
The user isn't the author.
In the case of proposals: only those that haven't reached the required threshold of votes, hiding as well those that the user is already following.
How to try it
In our local installation, if we haven't logged in, we can check at http://localhost:3000/proposals that the "recommendations" ordering isn't present:
Recommendations not logged in
Once we log in we see the menu, but because we don't aren't following any proposals we get the message "Follow proposals so we can give you recommendations" at http://localhost:3000/proposals?locale=en&order=recommendations&page=1
Recommendations no follows
After following any proposal with the "Follow citizen proposal" on the side menu: