Examine source code of Thunder Countdown Flow

{
  "manifest_version": 2,
  "name": "Thunder Countdown Flow",
  "version": "2.8.2",
  "description": "Chronometrer vos taches quotidiennes.",
  "permissions": [
    "storage",
    "notifications"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5dd08328-6a7a-4be4-82df-4b470c5d5314}",
      "strict_min_version": "128.0"
    }
  },
  "author": "White Technologies",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon-48.png"
    }
  }
}