Since Gitbook, probably say about 3.0.0 GitBook made it increasingly hard to add in footers, no idea why this was done. Anyways this theme makes it possible to define some vars in your book.json and use them in the footer, novel concept right?
In your book.json, include a vars section
{
"variables":
{
"defaultfoot": "hey look a footer"
}
}
This is the default theme for GitBook since version 3.0.0. It can be used as a template for theming books or can be extended.
