Examine source code of Wolt Notifier

{
  "manifest_version": 2,
  "name": "Wolt Notifier",
  "version": "1.0.2",
  "description": "Notifies when a Wolt restaurant is online.",
  "icons": {
    "48": "icon.png"
  },
  "permissions": [
    "alarms",
    "notifications",
    "https://*.wolt.com/*"
  ],
  "page_action": {
    "browser_style": true,
    "default_icon": "icon.png",
    "default_title": "Notify when online"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a197ef9d-5589-4a56-8dc6-92d99f08a779}"
    }
  }
}