Summary: If you're holding crouch and you are moving at the edge downwards, you can likely fall off of the staircase. This bug was fixed in Java, but hasn't made the cut on Bedrock.
Steps to reproduce:
Make a big staircase with stairs (any kind will work, did it with polished blackstone)
Go to the top of the staircase
Hold the crouch button
Move downwards at the edge
What should've happened: You stay on the staircase
What did happened: You fall off of the staircase
Images: Find them at MC-2404. I'm unable to provide a Bedrock Image of the bug.
Thank you for your report!
We're actually already tracking this issue at MCPE-88723, so I will resolve and link this ticket as a duplicate.
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