Bookmarklet of Scroll Event Logger

scrollEventLogger.bookmarklet.js

javascript:(function(){var a=document.createElement("div");a.style.cssText="position: fixed;bottom: 10px;right: 10px;padding: 10px;background: yellow;z-index: 2147483647";window.console={log:function(b){a.innerHTML+=b+"<br />\n"}};"loading"!==document.readyState?document.body.appendChild(a):document.addEventListener("DOMContentLoaded",function(){document.body.appendChild(a)},!1);var c=document.body.scrollTop,d=Date.now();window.addEventListener("scroll",function(b){b=document.body.scrollTop;var a=Date.now();
console.log([b-c,a-d,b,a].join(", "));d=a;c=b},!0)})();