Examine source code of Fatal Frame 2

{
  "theme": {
    "images": {
      "theme_frame": "Persona.jpg"
    },
    "colors": {
      "frame": "#443487",
      "tab_background_text": "#820000"
    }
  },
  "version": "2.0",
  "name": "Fatal Frame 2",
  "manifest_version": 2,
  "description": "I wanted to create one of these for my Firefox. You are welcome to it if you like."
}