/**
 * 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.
 *
 * @category Util
 * @returns A cleanup function that disconnects all observers.
 */
export declare function createOverflowObserver({ element, widthElement, onChange, hysteresisPx, }: 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;
    /**
     * Pixel margin required to flip the overflow state. Once overflowing, the content must fit
     * within `availableWidth - hysteresisPx` to flip back; once not overflowing, the content must
     * exceed `availableWidth + hysteresisPx` to flip on. Prevents rapid toggling from minute size
     * changes.
     */
    hysteresisPx?: number | undefined;
}>): () => void;