It sorta looks like the yeast clung to the side of the bucket, dried some, then peeled off. I guess that's possible, but I've never seen it happen myself.
It looks fine to me, your krausen (foam) collapsed and that is the foam left behind. Usually it makes a ring around the bucket right above the surface.
It's actually more krausen kurdles than yeast rafts. Yeast rafts float up from the bottom, these are just angular bits of the remainder of the krausens. Some yeasts when the krausen breaks from more angular chunks. It's fine.