/**
 * Copyright Aquera Inc 2025
 *
 * This source code is licensed under the BSD-3-Clause license found in the
 * LICENSE file in the root directory of this source tree.
 */
export declare class ComboboxPortalManager {
    private portalContainer;
    private originalListboxParent;
    private measuredPopupHeight;
    private component;
    private cleanupAutoUpdate;
    private currentPlacement;
    constructor(component: any);
    get portalContainerElement(): HTMLElement | null;
    private createPortalContainer;
    private computePosition;
    private fallbackPositioning;
    private extractStylesAsCSS;
    private injectStyles;
    setupPortal(): void;
    cleanupPortal(): void;
    updatePosition(): void;
    resetMeasuredHeight(): void;
    resetScrollPosition(): Promise<void>;
}