Examine source code of WebTime Reminder

{
  "manifest_version": 2,
  "name": "WebTime Reminder",
  "version": "1.0",
  "description": "Reminds you to manage time spent on websites.",
  "permissions": [
    "tabs",
    "storage",
    "notifications",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f7ae0e65-3d3f-429a-8a51-9378b52862d5}"
    }
  }
}