export function domReady( callback: () => unknown ): void {
	if ( typeof document === 'undefined' ) {
		return;
	}

	if (
		document.readyState === 'complete' || // DOMContentLoaded + Images/Styles/etc loaded, so we call directly.
		document.readyState === 'interactive' // DOMContentLoaded fires at this point, so we call directly.
	) {
		return void callback();
	}

	// DOMContentLoaded has not fired yet, delay callback until then.
	document.addEventListener( 'DOMContentLoaded', callback );
}