Examine source code of Website Time Tracker

{
  "manifest_version": 2,
  "name": "Website Time Tracker",
  "version": "2.4.0",
  "description": "Keeps track of when and where you spend your time",
  "icons": {
    "30": "icons/stopwatch.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_icon": "icons/stopwatch.png",
    "default_title": "Time Tracker",
    "default_popup": "popup/timer.html"
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8cb7263e-2e2d-4844-987e-6ea6240a6fdb}"
    }
  }
}