Is there any non-polling way to detect when a DOM element's size or position have changed?

Question

For a long time, I\'ve been looking for a way to detect when a DOM element\'s size or position has changed. It could be because the window resized, or because new child elements

Answer 1

As of 2019, you have access to:

• ResizeObserver to fire callback on size change. Be careful here, it's not supported everywhere yet.
• MutationObserver that could be used for position, but I guess that's a bit overkill. Well supported though.
• IntersectionObserver as a bonus, that allows you to check for intersection with ancestors. Extremly useful to optimize stuff, especially in WebGL. This is pretty well supported.