This has been driving me a little batty all day and I haven't been able to find where anyone else has documented this discrepancy.
window.getComputedStyle(el).height
See http://jsfiddle.net/ZwF9H/6/ for the demo.
What I am expecting is that window.getComputedStyle() should return the same computed height value between all browsers. Internet Explorer 11 is doing something different. (Actually, IE 9 and 10 are as well, but IE 11 was the first one I could get the dev tools to work in.)
For all other browsers, the computed height is the height set in the css whether it be in the stylesheet or inline on the textarea element.
IE11 is ignoring the box-sizing: border-box declaration and subtracts the padding and margin, which I think is incorrect.
Is this a bug, am I doing something wrong, is it a know fact that IE11 returns computed values differently?