Examine source code of wxs.us Weather

{
  "manifest_version": 3,
  "name": "wxs.us Weather",
  "short_name": "wxs.us",
  "version": "1.0.1",
  "description": "Free US weather from wxs.us: temperature on the toolbar, and a popup with the forecast, alerts, rain nowcast, and air quality.",
  "browser_specific_settings": {
    "gecko": {
      "id": "extension@wxs.us",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "locationInfo"
        ]
      }
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "action": {
    "default_title": "wxs.us Weather",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "background": {
    "scripts": [
      "shared.js",
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "permissions": [
    "storage",
    "alarms",
    "notifications"
  ],
  "host_permissions": [
    "https://t.wxs.us/*"
  ]
}