When using ProjectE's Ring of Arcana in Harvest mode, Hopping Bonsai Pots will disappear at random intervals, despite having soil and a sapling. They do not drop on the ground as an item, rather just delete themselves from the world.

Sorry, I'm personally not supporting any versions below the upcoming 1.18.1 version.
Maybe someone else wants to pick things up for older versions - I simply don't have the time.