I had a stack of 13 nether quartz, and I wanted to put them in my chest. I quick moved the item into the chest, and it turned into a stack of 1 nether quartz. I repeat, from 13 to 1, I checked all my chests, looked over everything twice, the missing 12 are nowhere to be found. I've never had an issue with this before, so now I'm a little worried about moving objects into my chest.