The bug
Player doesn't adjust their heights when opening a shulker box while standing on the shulker box and having a block above their heads, unlike pistons when a block is pushed into the player.
How to reproduce
Place a shulker box and stand on top of the shulker box
Place a block above you either manually or using the command "/setblock ~ ~2 ~ stone"
Open the shulker box and notice the player's height isn't adjusted and the player basically falls down into the shulker box
Linked issues
is duplicated by 10
relates to 2
Comments 4
Duplicate of MC-107946?
Can confirm in 1.16.5