Examine source code of download auto resumer

{
  "manifest_version": 2,
  "name": "auto resumer",
  "description": "when download interrupted, this addon make download resume.",
  "version": "0.0.1",
  "icons": {
    "64": "icons/icon.png"
  },
  "background": {
    "scripts": [
      "background_script.js"
    ]
  },
  "permissions": [
    "downloads",
    "alarms",
    "storage"
  ],
  "browser_action": {
    "default_icon": {
      "64": "icons/icon.png"
    },
    "default_popup": "browserAction/index.html",
    "default_title": "AutoResumer"
  }
}