When creating a "water elevator" by placing soul sand, then water source blocks on top, random water source blocks of the elevator will turn transparent. Bubbles and effects remain.

This occurs randomly through the stack of water blocks above the soul sand. eg: If you stack 10, randomly some of the 10 will change.

Placing a water source block with a gap between it and the stack, the blocks show the water properly.

Eg: (Shown horizontally, but should be vertical.  SS=Soul Sand, WB=Water Block)

SSWBWBWBWBWB

Some or all of the WBs will be transparent.

The placement of the one that overrides is (The gap is important):

SSWBWBWBWBWB  WB