Examine source code of WaybackURL

{
  "manifest_version": 2,
  "name": "WaybackURL",
  "version": "1.0.1",
  "description": "Get history of urls from wayback machine.",
  "browser_specific_settings": {
    "gecko": {
      "id": "hoseinshurabi@gmail.com"
    }
  },
  "icons": {
    "16": "icon.png"
  },
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "WaybackURL",
    "default_popup": "popup/popup.html"
  }
}