Countdown Timer

manifest.json

{
  "update_url": "http://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Countdown Timer",
  "description": "Offline Countdown Timer.",
  "version": "0.7",
  "app": {
    "launch": {
      "local_path": "main.html"
    }
  },
  "icons": {
    "16": "icon_16.png",
    "48": "icon_48.png",
    "128": "icon_128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}