Examine source code of Maculous

{
  "theme": {
    "images": {
      "theme_frame": "Mac.png"
    },
    "colors": {
      "frame": "#f0afaf",
      "tab_background_text": "#f22c2c"
    }
  },
  "version": "2.0",
  "name": "Maculous",
  "manifest_version": 2,
  "description": "App-les"
}