https://www.techradar.com/news/facebook-now-lets-you-disconnect-third-party-apps-in-bulk

In the wake of the Cambridge Analytica data scandal, in which information from more than 50 million Facebook users was harvested without permission, it's a good time to check which organizations have access to your details and remove any you aren't happy with. 

Until now it was necessary to select each one individually and view its details before disconnecting it. If you've used Facebook for a long time, you might have authorized dozens of apps over the years, making that a long and arduous process.