Earlier today, a Queen Wasp Hide dropped at the final fight of Greater Hives.
I then went to create a way to store these items, so I renamed a backpack "Boss Stuff". When I moved the hide into the backpack, the hide went missing.
At first, I figured I must have simply dragged it to another backpack. I looked, couldn't find it. Then I couldn't figure out for the life of me what happened.
I then looked at the backpack, and saw that the weight of the backpack is 3.8 stones. A clean one is 3 stones, and the hide was 0.8 stones if memory served me right. So even though the backpack appears to be empty when I look in it, it appears that the item is still recorded inside of it but the text went invisible.