Examine source code of Weather Add On

{
  "manifest_version": 2,
  "name": "My Weather Extension",
  "version": "1.0",
  "description": "Get the weather information for your location.",
  "icons": {
    "48": "icon.png"
  },
  "permissions": [
    "geolocation",
    "https://api.weatherstack.com/"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Weather Information",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{fc16a74a-0242-4f2f-a4b6-fb5ffecdf72f}"
    }
  }
}