Examine source code of Holiday Countdown

{
  "name": "Holiday Countdown",
  "manifest_version": 2,
  "version": "4.0",
  "theme": {
    "images": {
      "theme_frame": "holidaycountdownHCustom.jpg"
    },
    "colors": {
      "frame": "rgba(237, 222, 171, 0)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(0, 0, 0, 0)",
      "bookmark_text": "rgba(0, 0, 0, 1)",
      "toolbar_field": "rgba(0, 0, 0, 0)",
      "toolbar_field_text": "rgba(0, 0, 0, 1)",
      "tab_line": "rgba(255, 0, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0727962f-2d28-4684-a60a-99b1e283b8f2}"
    }
  }
}