When I towered up 27 blocks or higher, the chickens I had in a pen disappeared from sight, but were still there when I came back down.

Please note this does not affect all entities as the cow I had for my milk supply was still visible at any height

I expected to see the chickens in their pen. But i saw the chickens disappear from sight.

Reproduce by:

1. Find chicken.
2. Tower up a minimum of 27 blocks.