Reddit Contextualizer adds a lightweight activity summary to Reddit’s user hovercards. When you click on a comment author's username in a comments section, you’ll see which subreddits that user has participated in over the past year or so. (Data current through November 2025.)
The extension uses only publicly-available Reddit data. NSFW subreddits and very new communities are excluded to help preserve privacy.
Reddit Contextualizer doesn’t track you or clutter the interface. It simply adds a little data to an existing UI panel to help you better understand conversations as they happen.
