Its exactly as it sounds.
Steps to Reproduce
-Build a diagonal railway track that leads down into open air (NOT a block, it must be open air)
-Ride a Minecart down this track
-Watch as the Minecart catches on the very edge that the bottom rail is connected to, and halts completely in velocity
Linked issues
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Comments 3

Can confirm, check the attached video. This bug also affects java: MC-113242
Updated steps on how to reproduce:
1. Build an elevated track, around 5 rails should suffice.
2. On one end of the track place a powered rail and place a block with a button, not only to power the track but to also prevent the minecart from derailing at that end.
3. At the other end of the track make sure that there's nothing blocking the way and that the minecart can fall off the ledge.
4. Place the minecart at the starting point (the end with the powered rail), and power the rail.
Observed results:
The minecart will derail too early, causing it to stay floating midair.
Expected results:
The minecart should be able to be ridden off the ledge, and fall on the blocks below.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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