Closely relates to MC-256393.

The bug

When the obsidian platform in the End is regenerated, it also regenerates a cuboid of air above it. This results in any blocks within this cuboid beforehand being broken. Despite this, no particles of those blocks, nor their breaking sounds, will ever happen.

How to reproduce

1. Set up a device near an end portal to continuously send entities through it
2. Enter the End yourself
3. Place a block atop the obsidian platform
4. Wait for the next entity to enter The End

Expected results

The block you placed would turn into a bunch of block particles and play a breaking sound.

Actual results

It gets wiped from existence entirely.