Examine source code of Luminous 4

{
  "theme": {
    "images": {
      "theme_frame": "FireFox-Persona-12.jpg"
    },
    "colors": {
      "frame": "#556689",
      "tab_background_text": "#cccccc"
    }
  },
  "version": "2.0",
  "name": "Luminous 4",
  "manifest_version": 2,
  "description": "Dark dusty blueish gray with soft pastel illuminate accents"
}