Examine source code of DayTracker

{
  "manifest_version": 2,
  "name": "DayTracker",
  "author": "Himanshika Rawat",
  "version": "1.0.2",
  "description": "Extensry is a super cool extension that greets you with a message according to the time of the day and shows different background on page refresh. With Extensry you can set your main/focus task of the day ansd also create your own todo.",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{695f173a-e3e6-4f77-abac-39387aee8584}"
    }
  }
}