This is not much of an issue, but it's still weird. The picture is fairly self-explanatory, but for context, this is a stump with a log that generated with the log part above a river.

How to reproduce:

1. Make a world with the seed -4934109026671495692
2. Go to the coordinates X: 496 Y: 67 Z: -283
3. Behold the floating log. I'm pretty sure one of the splash messages is, and I quote, "DON'T LEAVE TREES FLOATING!!!", so an alternate fix to this bug is just to remove that message.

Edit:
Apparently there's another one in the same world? It's somewhat less broken from one way of looking at it, but it still looks really weird, since it's on top of a piece of grass. The coordinates for that are 461 81 -330.