Examine source code of KyotoWeather

{
  "manifest_version": 3,
  "name": "KyotoWeather",
  "version": "1.0",
  "description": "A weather extension providing forecasts for Kyoto",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "539d788b0af3418e9073d80bff7ebe63@example.org",
      "strict_min_version": "42.0"
    }
  }
}