I logged off in a world for like, 20 seconds. I had a full inventory which mostly consisted of beds, and also my normal gear, and a Shulker box filled with more brown beds. After I logged back into the world, my inventory got wiped clean. My armor and inventory slots, my off hand, my hot bar, even my experience bar was wiped. At first I thought I died, but that couldn't have been the case, but it was mid day, and I was sitting inside my house. I genuinely don't know how to replicate the problem nor do I know how it happened.