This type of modding allows you to customize and add content within the existing game structure using DFD's configuration files. This way you can modify things such as character editor skin tone colors or homebrew 5e content (Class Features, Weapons, Monsters, etc.)
Configuration & Content Modding
This deeper dive into DFD’s mechanics involves direct modifications to the game's codebase, offering a deeper level of customization at the expense of complexity (and the need for programming knowledge).