/** MIME / accept fallback for the thumbnail view (image-only upload mode). */
export declare const THUMBNAIL_ACCEPT = ".jpeg, .jpg, .png, .gif, .webp, .heic";
/**
 * Resolve the display name for a file item, preferring the (possibly renamed)
 * `attributes.targetFilename`, falling back to the underlying File, and finally
 * a localized "unknown file" label.
 */
export declare function getDisplayFilename(item: {
    file?: File | null;
    attributes?: {
        targetFilename?: string;
    };
}, fallback?: string): string;