When you get into a boat and ride up columns of bubbles, you get thrown out of the boat even when you don't press anything.
Link to video footage where I showed everything in detail: https://youtu.be/X5VJYtv3CLo
Step by step to do tis bug:
Rebuild the structure on the screen
Take a boat and and ride into the water colomn
don't press anything and you'll thrown out of the boat
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Thank you for your report!
However, this issue is Working as Intended.
The report you have submitted is working as intended: MC-89944 (You cannot be in a boat underwater in both Bedrock and Java editions).
Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
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