Use requestAnimationFrame instead of setTimeout
All animations in Highcharts use setTimeout. A new feature, requestAnimationFrame (https://developer.mozilla.org/en/DOM/window.mozRequestAnimationFrame) optimize all animations (CSS3, SVG, JS) to have a smooth rendering.
More explanation : http://paulirish.com/2011/requestanimationframe-for-smart-animating/
Added in the code base for Highcharts 6: https://github.com/highcharts/highcharts/commit/7ad0d20b5c3197286e859ef830316f47187cfcc0
Any example of using requestAnimationFrame here?