Boat got bugged

This boat got bugged:

What's happened?:

I made an experiment and I saw this:

How to reproduce a bug?:

1. Make a pulling bubble column (magma)
2. Place a boat over bubble column
3. Fast come and stand on magma blocks
4. Wait until boat go to sink
5. Block the boat's road
6. You can leave magma blocks
7. And yeah... Boat will stay forever 

Attachments/Screenshots:

Well, I can't attach the screenshot here, so here's your screenshot on IMGUR:

https://imgur.com/a/WeZCxWc