Since v1.30 whenever you pick up an item with for example your gun in your hand, the character doesn't put the gun on it's back but drops it on the floor. This happens with any item you have in your hands, even when they have slot assigned in your storage. Have lost several items due to change in behavior.

Put items in your storage, place them in your hand and try picking up new items.

Item that is your hands, with a slot assigned in your storage, should be placed back your storage instead of being dropped.