Examine source code of Agendum

{
  "manifest_version": 2,
  "name": "Agendum",
  "version": "0.0.1",
  "chrome_url_overrides": {
    "newtab": "newtab.d2eda5d2.html"
  },
  "browser_action": {
    "default_icon": "icon.6e8a65a6.png",
    "default_title": "Agendum",
    "default_popup": "popup.720e8773.html"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{ea747f91-79f3-4de6-b4ee-0a80ea9a5ece}"
    }
  }
}