I discovered a bug that allows you to go under the ground thanks to a shulker box

how to reproduce

1. make a hut under the ground just an example

2.stack several shulker boxes between them there should be one shulker at the grass block layer

3.break the other shulker boxes without breaking the shulker on the surface of the grass blocks

4.place a block 2 blocks from the shulker

5.place you on the shulker open it and you will slide through

follow the steps otherwise with the photos