import createCache from '@emotion/cache';
declare class SingletonIframeManager {
    private zIndex;
    private pointerEvents;
    private persistentIframe;
    iframeEmotionCache: ReturnType<typeof createCache> | null;
    iframeLoadPromise: Promise<void> | null;
    private iframeLoadResolver;
    private removeGlobalTransformSync;
    private referenceCount;
    constructor(zIndex: number, pointerEvents: string);
    private create;
    acquire(): Promise<{
        iframe: HTMLIFrameElement;
        emotionCache: NonNullable<ReturnType<typeof createCache>>;
    }>;
    release(): void;
}
export declare const modalIframeManager: SingletonIframeManager;
export declare const toastIframeManager: SingletonIframeManager;
export {};