ResizeObserver now available in Chrome

Chrome 64 includes ResizeObserver:

ResizeObserver notifies you whenever an element’s size changes, and provides the new height and width of the element, reducing the risk of layout thrashing.

To use it create a new instance of it, and then make it observe one or more elements:

var ro = new ResizeObserver(entries => {
  for (let entry of entries) {
    const cr = entry.contentRect;
    console.log('Element:', entry.target);
    console.log(`Element size: ${cr.width}px x ${cr.height}px`);
    console.log(`Element padding: ${cr.top}px ; ${cr.left}px`);
  }
});

// Observe one or multiple elements
ro.observe(someElement);

New in Chrome 64: ResizeObserver →
ResizeObserver: It’s Like document.onresize for Elements →