Examine source code of Tab Tools

{
  "name": "Tab Tools",
  "description": "add todo,main-focus,weather and events",
  "version": "1.0.2",
  "manifest_version": 2,
  "author": "Deepak Goyal",
  "browser_action": {
    "default_popup": "index.html",
    "default_title": "New Tab"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{98ff715c-650a-44ba-a714-4b39666544c7}"
    }
  }
}