Examine source code of Weather Forecast v2

{
  "manifest_version": 2,
  "name": "Weather Forecast",
  "version": "1.0",
  "description": "Get the current weather forecast for your location.",
  "permissions": [
    "geolocation",
    "activeTab"
  ],
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1d632e6e-bd37-44e0-bb8b-a268b37f7741}"
    }
  }
}