Full shulker boxes stored in chests of 27 stacks of blocks will occasionally render as:

"Shulker Box

and 22 more..."

and then contain nothing when placed down

Is not consistent within a given chest, as some boxes in the same chest still look correctly filled. Additionally not just chests in one block space (such as a chunk boundary). Have not yet found a case of a partial box being emptied but this may be possible

This has effected roughly half to 2/3 of my bulk resources