(Caves & Cliffs experimental) Rideables like boats can disappear after dismounting

Rarely, when you dismount from rideables like boats, they can vanish. You cannot interact with them, but the boat itself is still there, as you cannot place blocks on that spot. If you reload the game, the boat will appear again.

As an added note, it seems that if you dismount from a boat near land, you can sort of go through blocks.