paulirish

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

• elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

p3t3r67x0

Styling native elements

Native HTML controls are a challenge to style. You can style any element in the web platform that uses Shadow DOM with a pseudo element ::pseudo-element or the /deep/ path selector.

video::webkit-media-controls-timeline {
  background-color: lime;
}

video /deep/ input[type=range] {

gblazex

IMPORTANT

Please duplicate this radar for a Safari fix! 
This will clean up a 50-line workaround.

  rdar://22376037 (https://openradar.appspot.com/radar?id=4965070979203072)

//////////////////////////////////////////////////////////////////////////////

(Now available as a standalone repo.)

tvandervossen

env = (function() {
  var flags = {}, ua = navigator.userAgent, el = document.createElement('div'), video = document.createElement('video'), audio = document.createElement('audio'), root = document.documentElement, i
  function flag(names) {
    names = names.split(' ')
    for (i = 0; i < names.length; i++)
      flags[names[i]] = true
  }
  function classnames() {
    var names = [], name
    for(name in flags) if (flags.hasOwnProperty(name))

paulirish

// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

// requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel

// MIT license

(function() {
    var lastTime = 0;
    var vendors = ['ms', 'moz', 'webkit', 'o'];