Access the dimensions and position of this element's content + padding box.
This returns a rectangle with the dimenions actually available for content in this element, in pixels, regardless of this element's box-sizing property. Unlike getBoundingClientRect, the dimensions of this rectangle will return the same numerical height if the element is hidden or not. This can be used to retrieve jQuery's innerHeight value for an element. This is also a rectangle equalling the dimensions of clientHeight and clientWidth.
Important note: use of this method will perform CSS calculations that can trigger a browser reflow. Therefore, use of this property during an animation frame is discouraged. See also: Browser Reflow