Plainly and simply, moving items to vicinity makes them disappear immidiatly, and always. It makes it hard to use medical kits or any kind of container, or even switching backpacks.
Its possible to retain the items from disappearing if you replace an item ontop of another item already on the ground.
Drop any item on the ground
I have experienced this bug, however after a few seconds, the item eventually appears either on the ground nearby, or at the location where it originally spawned.
Hello,
This is a duplicate report, please refer to: #1074 for further information and development.
Thank you for your feedback.