In my world, I live in a village house that had a naturally spawned "Loot Chest," which looks like a normal vanilla chest. I believe the bug lies within it being unsearchable/uncraftable, but after I had completely filled it over the course of several dozens of days of mob grinding, I intended to destroy it because it would not extend with a new "Chest" for a double chest, just stayed separated. But, when I destroyed it, only a "Chest" dropped, and my face went pale lol, as I don't have cheats active. So yeah, when "Loot Chest" is broken, all items inside disappear...

this is a known thing due to lootr.

we have a warning on our discord regarding it but haven't gotten around to putting it in the quest book yet.