Examine source code of Homepagr

{
  "name": "Homepagr",
  "version": "5.0",
  "manifest_version": 2,
  "short_name": "Homepagr.com browser extension",
  "description": "This extension sets your \"new tab\" page to your bookmarks, and allows you to save bookmarks from the toolbar.",
  "homepage_url": "https://www.homepagr.com",
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "browser_action": {
    "default_icon": "icons/page-32.png"
  },
  "background": {
    "scripts": [
      "bookmark.js"
    ]
  },
  "permissions": [
    "activeTab",
    "storage",
    "tabs"
  ],
  "options_ui": {
    "page": "options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0c864efe-8f3c-4abb-820a-dbdaa16f2756}"
    }
  }
}