@openproject/primer-view-components/app/components/primer/utils.js

ViewComponents of the Primer Design System for OpenProject

// Waits for condition to return true. If it returns false initially, this function creates a
// MutationObserver that calls body() whenever the contents of the component change.
export const observeMutationsUntilConditionMet = (element, condition, body) => {
    if (condition()) {
        body();
    }
    else {
        const mutationObserver = new MutationObserver(() => {
            if (condition()) {
                body();
                mutationObserver.disconnect();
            }
        });
        mutationObserver.observe(element, { childList: true, subtree: true });
    }
};