Examine source code of Tab Spinner

{
  "manifest_version": 2,
  "name": "Tab Spinner",
  "version": "1.3",
  "description": "Rotate tabs every few seconds and reload them before switching (optional).",
  "permissions": [
    "tabs",
    "storage",
    "alarms"
  ],
  "background": {
    "scripts": [
      "background.js",
      "open-tab.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Tab Spinner",
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "icons": {
    "16": "icon.png",
    "32": "icon.png",
    "48": "icon.png",
    "128": "icon.png"
  },
  "applications": {
    "gecko": {
      "id": "tabspinner@example.com"
    }
  }
}