@stimulus-library/mixins/dist/use_resize_observer.js

A library of useful controllers for Stimulus

import { useMixin } from "./use_mixin";
export function useResizeObserver(controller, element, handler, options) {
    handler = handler.bind(controller);
    const observer = new ResizeObserver(handler);
    const setup = () => observer.observe(element, options);
    const teardown = () => observer.disconnect();
    useMixin(controller, setup, teardown);
    return teardown;
}