Affects Version/s: Minecraft 1.13-pre2
Fix Version/s: None
Using creating a water reservoir more than one block deep, then removing the top layer, the lower levels of water should remain.
All water blocks are removed below the top most water block that was placed by the player and then removed.
The Targeted Fluid of a water block is changed to flowing_water and falling to true if a player places a water block on top of it. Easy to recreate by making a 3 tall column of blocks and placing 3 water against it from the floor up. then remove the top water block and all of the water is deleted.