Examine source code of Wonderful Days

{
  "theme": {
    "images": {
      "theme_frame": "My-Persona-Image5.jpg"
    },
    "colors": {
      "frame": "#228b22",
      "tab_background_text": "#00ff00"
    }
  },
  "version": "2.0",
  "name": "Wonderful Days",
  "manifest_version": 2,
  "description": "My first header, it also goes well with a bright yellow text color."
}