Upon spawning into either a new or existing world, the chunks & blocks will load as per normal. However, after roughly 30 seconds (or more) of playing the world, all blocks (i.e. dirt; trees; glass; etc.) and some items (i.e. torches) will become completely blacked-out.

• Affected items in your inventory will be displayed as black squares
• The physical world removes all block outlines (as all blocks become the same colour as the outlines), hence making it unable to determine the difference/navigate between blocks.

Changing the language seems to be the most effective temporary solution to restoring all blocks to normal. However, the blocks will inevitably return to its blackened state.

NOTE: I updated my Java to the most recent version and tested Minecraft once more. It took several minutes before the world's blocks blackened again.