so in your settings you have a field to select which items to incress the stack size for, is it possible to only incress stack size of barrels? and if so how?
i did try putting barrel in that field and it had no effect.
Great question, barrel has itemType of "item", but that will change a bunch of other stuff.
This provided me a good insight to the problem why would anyone know itemTypes and besides that it's more logical to use names of items instead.
I'll work on that in the next update.