Summary:

When the player independently extinguishes and simultaneously enters powder snow, the powder snow will disappear, but if you perform any action while aiming at the adjacent block of disappeared snow, the snow will appear. This also happens when you enter two blocks at the same time. One block disappears and the other becomes phantom.

Steps to reproduce:

(1)

1. Place the two powder snow horizontally.
2. Set yourself on fire.
3. Enter two blocks at the same time.
4. Aim at adjacent blocks and take some action (for example, start eating).

(2)

1. Go creative (you can do it in survival, but it's difficult to reproduce).
2. Set fire to the block.
3. Skip one block from the fire and place powder snow.
4. Enter powder snow quickly.
5. Aim at adjacent blocks and take some action (for example, start eating).

Observed results:

Powder snow will become invisible (in the first version, one block should "melt" this is how it should be).

Expected results:

There should be no phantom blocks.

Notes:

In one place, the first method works only once. To repeat exactly in the place where the blocks disappeared, you need to re-enter the world.

Video:

Steps to reproduce (1) Minecraft 2021-04-09 15-27-48.mp4

Steps to reproduce (2) Minecraft 2021-04-09 15-16-09.mp4