Examine source code of Reading Timer

{
  "manifest_version": 2,
  "name": "Reading Timer",
  "version": "1.0",
  "description": "Set a timer to track your reading sessions.",
  "permissions": [
    "storage",
    "notifications"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Reading Timer"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7c030e72-2d3a-45fe-aad0-b527f725a7fc}"
    }
  }
}