/**
 * Creates an observer that monitors whether an element's content overflows its visible width. Uses
 * a ResizeObserver for size changes and a MutationObserver for DOM content changes.
 *
 * @returns A cleanup function that disconnects all observers.
 */
export declare function createOverflowObserver({ element, widthElement, onChange, }: Readonly<{
    /** The element whose `scrollWidth` is measured for content size. */
    element: Element;
    /**
     * Optional separate element whose `clientWidth` is used as the available width. Defaults to
     * `element`. Useful when `element` may be collapsed but the available width should come from a
     * parent.
     */
    widthElement?: Element | undefined;
    onChange: (isOverflowing: boolean) => void;
}>): () => void;