Examine source code of Webmails Guide

{
  "browser_action": {
    "default_icon": "img/icon_128.png",
    "default_popup": "html/popup.html",
    "default_title": "Webmails Guide"
  },
  "description": "All information about webmails",
  "icons": {
    "16": "img/icon_16.png",
    "128": "img/icon_128.png"
  },
  "manifest_version": 2,
  "name": "Webmails Guide",
  "version": "1.1"
}