Problems sorting modded inventories

[ghost]

MC 1.12.2, IT 1.63
The Arcane Archives radiant chest allows for stacks 4x the normal stack size, so you can stack 4 things that aren't normally stackable or 256 of things that can go to 64. When I try to sort the inventory, it splits the large stacks. If the inventory is full and some stacks are over their normal limit it won't sort at all.