Examine source code of Cool letters

{
  "theme": {
    "images": {
      "theme_frame": "nivafrperson.jpg"
    },
    "colors": {
      "frame": "#2c86b0",
      "tab_background_text": "#c48e21"
    }
  },
  "version": "2.0",
  "name": "Cool letters",
  "manifest_version": 2,
  "description": "Cool Letters!"
}