i was playing around with falling anvils when I saw the height of a church and made a anvil fall from the top block. It would fall, but when it would hit the ground about a second later it bounces back up about 2 blocks and only gets slightly damaged. This is annoying to me because I wanted to drop them from a high height and see if they would break. I tried this multiple times to see if it was a one-time thing, but sure enough, it wasn't. I don't think bouncing anvils would make any sense in Minecraft nor any other game, so I'm pretty sure it's a bug.