When loading into the world, it starts off invisible

Build: 423437
Summary:
Loading a world, it takes seconds sometimes when entering the game for all the blocks to render around the player. You are able to see through the world and to other tile entities.
Impact:
Ability to see through the world could allow for cheating and seeing things that should not be seen such as hidden areas or scratch pads for map making where we clone things in and out from. Also looks unprofessional.
Repro Steps:
1.Load a world.

Observed Results: Can see through the blocks
Expected Results: Should be able to see the blocks as soon as the world starts. Might even make sense to just have the gui overlays of world loading up for a second or two longer if that means not seeing through the world like this.
Screenshots/Videos attached: no