When I was trying to test issues created by others i needed to place a block above the ocean. I did /setblock ~ ~ ~ minecraft:iron_block. The block as invisible. And the blocks placed next to it too. I tested if the potion of night vision was the problem, but without that potion effect they were still invisible.

How to reproduce:
Build blocks in an empty chunk. Build a pillar high up. When reaching an empty chunk, the blocks will dissapear.

On the F3 screen on the right side they showed the model name as: IDUNNOMYNAME.

EDIT: when i leaved and joined my world everything was normal again. Even when i tried to reproduce it with the setblock and stuff.

EDIT EDIT: got it again above a certain y level. see 3th screenshot.

EDIT EDIT EDIT: it happens in chunks with no blocks in it.

again edit: still happens in 14w25b. And by the way, I dont think this is a duplicate, because where this should be a duplicate from are other issues, or am I wrong?