Summary:

When entering my main nether portal, the game starts applying suffocation damage to player until the world fully loads.   If the world loads in too slowly, such as at my main spawn point with a lot of redstone devices, you can suffocate before the loading screen finishes.  

Observed Results:

The player starts suffocating before the world loads fully.  If world loads too slowly on a device, player suffocates to death.

Expected Results:

The game should suffocate someone for traveling through a nether portal.  Until the player has control and can see the world they should be unable to be damaged or be interacted with.

Systems tested on:  Android, iOS, and Nintendo Switch.