Examine source code of Shipping icon

{
  "manifest_version": 2,
  "name": "Shipping icon",
  "version": "1.0",
  "description": "Shipping icons often represent delivery, courier, logistics activities, and often appear in e-commerce applications...",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html",
    "default_title": "Click me!"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{027abe66-e7f9-4457-8ac7-784aad4544ee}"
    }
  }
}