Waterlogging

Waterlogging is a mechanic that allows water to occupy the same space as all blocks that do not occupy a full block. This can be caused by using a water bucket on waterloggable blocks (blocks that have air, such as slabs). This can also be caused without a water bucket with a debug stick.

Mechanism
In Java Edition, certain blocks have a tag which can be either.

In Bedrock Edition, waterlogging is handled by the game's layers system. Through editing, any block can be waterlogged, as well as other things such as placing multiple slabs into a single block.

Behavior
Section may be incomplete.

See report for more info.