Examine source code of Local Time Converter

{
  "manifest_version": 2,
  "name": "Local Time Converter",
  "version": "1.0",
  "description": "Display local time at your destination.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{79e85f45-51fc-4dd8-8711-11240f185661}"
    }
  }
}