Endermans die from a 43 block fall but they supposed to survive it with 1/2 heart.

Enderman’s HP is 40, and combined with the safe_fall_distance (3), you get 40+3=43. This seems intentional, and the previous behavior seems like a bug.
A solution for the farm would be making the fall 42 blocks, not 43.
Probably caused by the fix of MC-167125.

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Thanks for the feedback but I noticed it now. It applies for every mob(I think bcs it applied to skeleton).

I also did the solution with testing in my world but I wonder will it be fixed?

I need you to provide steps to reproduce as per my previous comment