A quite popular mod, ice and fire, causes problems with the body; it adds a gorgon that turns players to stone statues, with this mod in addition, a petrified corpse is created - deleting all items except those worn by the player (main & second hand, armor)

should be easy to recreate, i got that bug running forge 1.12.2-14.23.5.2847, ice and fire 1.9.1, lootable bodies 2.4.0