How to create:
Place some powered rails in 1 deep water and then place 1 minecarts in it
Ride the minecart for few blocks and jump out
There you have it minecart gone
How to fix it:
Press F3 + B to show hitboxes and the minecart will appear back
It may stay it may go away as soon as you disable hitboxes
What should happen:
The Minecart should not disappear (Though the entity is there and u can interact with it)
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duplicates
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likely duplicates MC-197328

oh ok, I have lost my world in a PC corruption/Reset but I was able to create it again so here it is! ( Also I figured out that this only happens if the water is flowing and not stable)(The minecart needs to be moving and you need to directly look at it)
[media]Thank you for your report!
We're tracking this issue in MC-197328, so this ticket is being resolved and linked as a duplicate.
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Could you please provide a screenshot with the F3 screen enabled? Also, what's your entity render distance set to?