export declare const isViewTransitionSupported: boolean;
/**
 * Not a `document.startViewTransition()` polyfill,
 * just do nothing in the browser that does not support this API,
 * but returns the same interface as it supports.
 * @example
 * // For react, use `flushSync()` to synchronously set state
 * // (state changes is asynchronous by default)
 * startViewTransition(() => {
 *     flushSync(() => {
 *         setYes((prev) => !prev);
 *     });
 * });
 *
 */
export declare function startViewTransition(updateDOM: () => Promise<void> | void): ViewTransition;
/**
 * Shorthand function which call `flushSync()` in the internal.
 * You can use the prepare & cleanup function to toggle className
 */
export declare function startViewTransitionFlushSync(callback: VoidFunction, prepare?: VoidFunction, cleanup?: VoidFunction): void;