Face recognition, group photos of the same person

When I first used face recognition, I remember that I had a thumbnail for each person I had classified, and then I could click on the person and get all the images.

Something happened (I dunno I may have missclicked something) and now I see all the photos (like 1000+ pictures) in one grid. It's ugly to see and hard to navigate. How can I revert back and get the old visualization? I looked around and I can't find anything.

Thank you!