Blocks don't render when placed inside a empty chunk until reloading them with F3+a
Step to reproduce: Create or load a world, leave the area you joined the world by 3~4 chunks, take any block and build a tower until you find a chunk with no block inside.
Not every empty chunks don't render blocks but they are numerous so it's easy to find one.
Related issues
duplicates
Attachments
Comments

[media]

Empty chunks are just entirely broken in this snapshot. They seem to behave almost identically to how chunk errors worked in 1.8.