Examine source code of Package delivery icon

{
  "manifest_version": 2,
  "name": "Package delivery icon",
  "version": "1.0",
  "description": "The package delivery icon is commonly used in delivery, e-commerce, or shipping applications, meaning dispatch, shipping, or delivery.",
  "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": "{6a461813-736c-48fe-8aab-4643908b279f}"
    }
  }
}