/**
 * Hand the browser two frames so a pending store update actually reaches the
 * screen before we start the next long synchronous block.
 *
 * One frame is not enough: the first rAF callback runs *before* the paint of the
 * commit it triggered, so blocking there would freeze the UI showing the
 * previous state. Waiting for a second frame means the overlay is visibly on
 * screen when the block begins.
 *
 * The timer is not a nicety: a hidden or backgrounded tab never runs rAF
 * callbacks at all, so waiting on frames alone would stall the load until the
 * user came back to the tab. The frames are the fast path when visible; the
 * timeout is what guarantees the load always proceeds.
 */
export declare function yieldToPaint(): Promise<void>;
export declare function loadUrlIntoStore(url: string, onProgress?: (pct: number | null) => void): Promise<void>;
export declare function loadFileIntoStore(file: File): Promise<void>;