Examine source code of Simple Weather °C

{
  "manifest_version": 2,
  "name": "Simple Weather °C",
  "version": "1.1",
  "permissions": [
    "activeTab",
    "storage",
    "https://wttr.in/"
  ],
  "browser_action": {},
  "icons": {
    "48": "icone-default.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1aebeb00-1ab0-4a23-b4f8-deadf3844d79}"
    }
  }
}