Examine source code of Which Login did I use last time?

{
  "name": "Which Login did I use last time?",
  "description": "Keep forgetting which social login you used last time? This extension helps you remember it, by remembering for you.",
  "homepage_url": "https://whichlogin.com/?ref=extension",
  "manifest_version": 2,
  "version": "0.5.5",
  "author": "Peter Thaleikis",
  "page_action": {
    "default_title": "Which Login?",
    "default_popup": "popup.html",
    "default_icon": "assets/icons/gray.png"
  },
  "icons": {
    "48": "assets/logo_48x48.png",
    "96": "assets/logo_96x96.png",
    "128": "assets/logo_128x128.png"
  },
  "background": {
    "scripts": [
      "browser-polyfill.js",
      "background.js"
    ]
  },
  "permissions": [
    "history",
    "activeTab",
    "tabs",
    "storage",
    "notifications"
  ]
}