When a player & entity is in a boat they are then able to board a minecart. The Player is then unable to exit this minecart or boat without assistance from another player.
Reproduce:
1 - Push Entity in to Boat
2 - Player Get in Boat
3 - Row Boat in to minecart
Thank you for your report!
We're actually already tracking this issue in MC-113871, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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