Examine source code of Tracker

{
  "manifest_version": 2,
  "name": "Tracker",
  "version": "1.0",
  "description": "Tracs your time between websites",
  "icons": {
    "128": "icons/tracker-128.png"
  },
  "browser_action": {
    "default_popup": "view/index.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false,
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "permissions": [
    "tabs",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{104d0dbe-cad0-4795-af15-de5668fe2c93}"
    }
  }
}