I just been noticing some other weird glitches with blocks changing into other blocks. Have PMed Aikar the one I was able to replicate. What IS going on?
I haven't had this chest issue, but I have noticed that if I'm messing around and break stuff like flowers and whatnot it drops a stone block but then changes back to whatever the item is.
For me its just texture swap occasionally, I can open the chest and it goes back to the proper texture.
One time I was at a ender farm and I was harvesting seeds, but when they popped out they had the texture of smooth stone till I picked it up..