Examine source code of Shadow Cat

{
  "theme": {
    "images": {
      "theme_frame": "shadowcata.jpg"
    },
    "colors": {
      "frame": "#e0d9d9",
      "tab_background_text": "#fcfcfc"
    }
  },
  "version": "2.0",
  "name": "Shadow Cat",
  "manifest_version": 2,
  "description": "A cat in the shadow and licking himself in the mountain city of cats (Houtung) in Taiwan."
}