export type FullscreenElement = Element & {
    requestFullscreen?: () => Promise<void>;
    mozRequestFullScreen?: () => Promise<void>;
    webkitRequestFullscreen?: () => Promise<void>;
    msRequestFullscreen?: () => Promise<void>;
};
export type DocumentWithFullscreen = Document & {
    exitFullscreen?: () => Promise<void>;
    mozCancelFullScreen?: () => Promise<void>;
    webkitExitFullscreen?: () => Promise<void>;
    msExitFullscreen?: () => Promise<void>;
};
/**
 * Request fullscreen on `el` (or the document root). Resolves `true` when fullscreen
 * was actually entered, `false` when it was a no-op or blocked — e.g. inside an iframe
 * whose `allow` lacks `fullscreen` (SFDC embed / app host), where the browser rejects
 * with "TypeError: Disallowed by permissions policy". Swallowing that rejection keeps
 * it from surfacing as an unhandled rejection (IMPACT-WEB-NG-GH/GG).
 *
 * IMPORTANT: resolution does NOT mean fullscreen is active — callers that run side
 * effects on entering fullscreen (set state, broadcast events, reparent DOM, steal
 * focus) MUST gate them on the returned boolean.
 */
export declare function requestFullscreen(el?: FullscreenElement | null): Promise<boolean>;
export declare function exitFullscreen(): Promise<void>;
export declare function toggleFullscreen(element: FullscreenElement): void;
export declare function isFullscreen(): boolean;