In editor:
1 - place a player-vehicle somewhere and hit preview.
2 - Open player inventory while inside vehicle.
3 - Unload weapon of choice.
4 - Drag fitting magazine from vehicle inventory directly to weapon magazine slot.
5 - Observe that the magazine disappears into the void.
6.1 - Note: from here on and onward, you cant transfer stuff to the player inventory until death/restart.
6 - Try to move anything from any inventory to player inventory.
7 - Observe that nothing is transferred, and the item disappears.

This can also be reproduced with teammate inventory.

dev-1.39.129084