Fence disappears from inventory if you attempt to place a fence post against it with a mob attatched to you by a lead

If you leash a mob and place a fence post, then attempt to place another fence post against it, the lead will connect to the post and the post you are holding will appear to be deleted from your inventory. However, if you right-click with the same hotbar slot or interact with it in your inventory, it will reappear.