Overflow saves your settings in your own browser only. It has no account, no tracking and no analytics, and it doesn't send your settings anywhere.

One optional feature sends data: "Show dislike counts". It is off until you turn it on. When it's on, Overflow sends the ID of each YouTube video you open to the Return YouTube Dislike API (returnyoutubedislikeapi.com) to get the estimated dislike count. Nothing else is sent. Return YouTube Dislike's own privacy policy applies to that data. Turn the option off and nothing is sent.