As in title.
If I put any item that have stack in mob inventory, magically disappear one item of for example 34. If I put 100 of something, I will see 99 in mob inv, then if I will pull I will have still 99 but again if you will try put it in mob inv, you will get one less.
FAST EDIT
I had this problem with aloe. I tried with stone and it doesn’t disappear.