Examine source code of Package installation icon

{
  "manifest_version": 2,
  "name": "Package installation icon",
  "version": "1.0",
  "description": "Package installation icons in applications or operating systems often have the following characteristics: Open box icon + gear → represents software package management and adjustment.",
  "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": "{f8632458-761e-46ef-b7a7-ac2ad6afc2a9}"
    }
  }
}