Examine source code of Site Timer

{
  "manifest_version": 3,
  "name": "Site Timer",
  "version": "1.0.0",
  "description": "Tracks time spent on each website and shows a breakdown of your browsing habits.",
  "browser_specific_settings": {
    "gecko": {
      "id": "sitetimer2847@timetool.io",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "64": "icons/icon-64.png",
      "128": "icons/icon-128.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "64": "icons/icon-64.png",
    "128": "icons/icon-128.png"
  }
}