Backpacks for dummies: Slot Editor

A simple fork of Backpacks for Dummies that lets you configure the number of backpack slots via a config file.

Content (from Original Modpage)

Crafted using leather (and rope if farmers delight is installed), backpacks can be placed down as a block or worn on your chestplate-slot. They can be placed down or picked up quickly by shift-clicking.

Backpack dying: Backpacks can be dyed any color just like leather armor.

Placement on death: If they contain items, backpacks will place themselves down, they'll even float on water.