export declare class FirefoxLedgerBridge {
    iframe: any;
    bridgeUrl: string;
    constructor();
    unlock(hdPath: number[], hrp: string): Promise<{
        address: string;
        publicKey: string;
    }>;
    signTransaction(hdPath: number[], tx: any, hrp?: string): Promise<any>;
    _setupIframe(): void;
    _getOrigin(): string;
    _sendMessage(msg: {
        action: string;
        params: any;
    }): Promise<any>;
}