Every time I reopen a world, and look into a double chest that I have placed items in, and opened after reopening the world, I find multiple items are deleted. It seems to be in an area covering the bottom right area, and a bit past the halfway point vertically, and This is the extent I know, as I fill the chests in a certain order, starting from the top right. I do not know if it is the cause of addons, but in each case, the world was at least 200-255 MB in size. 

Steps to reproduce (from what I know)

1. Place a double chest, and place items of any type into it, preferrably filling it completely to see the full area that is affected.
2. 1.5. (May or may not affect things) get the world file size at least the size previously mentioned (200-255 MB+) 
3. Exit the world and re-enter.
4. Check the chest previously filled.

What is expected:

Chest retains all items placed into it, not losing any or deleting any.

What is observed:

All items in an area of the GUI of the chest is deleted completely.