Examine source code of Looking up

{
  "theme": {
    "images": {
      "theme_frame": "header.jpg"
    },
    "colors": {
      "frame": "#2f5c8f",
      "tab_background_text": "#c1c1c1"
    }
  },
  "version": "2.0",
  "name": "Looking up",
  "manifest_version": 2,
  "description": "Drawing inspiration from nature."
}