import { IFrameBridgeOptions, InternalIframeMessage } from './contracts';
/**
 * Default options for an IFrameBridge
 */
export declare const IFRAME_BRIDGE_DEFAULT_OPTIONS: Readonly<IFrameBridgeOptions>;
/**
 * Verifies if a message respects the format expected by an IFrameBridge
 * @param message
 */
export declare function isSupportedMessage(message: any): message is InternalIframeMessage;
/**
 * Generates the html content of an iframe
 * @param scriptUrl script to be executed inside the iframe
 * @param additionalHeader custom html headers stringified
 */
export declare function generateIFrameContent(scriptUrl: string, additionalHeader?: string): string;
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