What I expected to happen was...:
The boat disappears and you are teleported to the right place.

What actually happened was...:
You become invisible, you fall through the ground. When it reaches the height -66.05000 you stop and cease to interact with the world.

Steps to Reproduce

1. Put the boat abroad of the world.
2. Sit down in it.
3. Go to the edge of the world, sitting on the boat.