Mobs and players landing in 1-deep water take fall damage from certain heights that they should not take fall damage from, and do not take fall damage from certain heights that they should take fall damage from.
World save is attached.
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Thank you for providing the world download (It made it easy to test). I can confirm that the fall damage is inconsistent from varying heights when falling into 1 high water blocks. Windows 7
This issue still has not been fixed. I played with the snapshot because I wanted to develop my mob system. With a water source 6 blocks above the ground, fall damage is some non-increasing function of height, however, it is consistent. Every time I fall 55 blocks above the ground (49 above the water) I get 1/2 half heart of damage. If I fall 60 blocks in the same set up, I get 1 heart of damage. However, if I fall 61 blocks, I always get 0 damage. 62 blocks, always 1 heart. 63 blocks, 0. 64, 1. 65 blocks, always death. 66 blocks, always 1 heart. 68 blocks, always no damage. 70 blocks, death.
Block types represent what damage occurs when walking off block height into the tube with water 6 blocks above the ground.
Redstone: death
Spruce: 0 heart
Lapis: -1/2 heart
Sandstone: -1 heart
Not sure how old this topic is, but happening as of latest TU (52)