Blocks will either go invisible for a moment when placing slabs on hoppers.  Also when minning blocks have become completely see through.  I will provide screen shots.

What I expected to happen was...:
Not to see through solid blocks.

What actually happened was...:
Blocks became transparent.  Sometimes for a brief moment.  Sometimes until I mined out the block.

Steps to Reproduce:
1.  Strip mining at Y level 5

2.  Cleared the block and the space turned black but could also see glowing squid in the distance along with spider eyes.

3. Blocks stayed transparent till I mined the transparent bloack

4. Also when placing slabs on top of hopper's, the slab will become transparent with only the outline for a brief moment.  Then renders fully.  Happens a lot of other times off in the distance as well.  Just when running around the world.