/**
 * Update the kubeconfig context extensions in IndexedDB.
 * @param kubeconfig - The kubeconfig to store.
 * @param customName - The custom name for the context extension.
 * @param clusterName - The name of the cluster to update the kubeconfig context for.
 * @returns promise that resolves when the kubeconfig is successfully updated and stored.
 * @throws Error if IndexedDB is not supported.
 * @throws Error if the kubeconfig is invalid.
 */
export declare function updateStatelessClusterKubeconfig(kubeconfig: string, customName: string, clusterName: string): Promise<void>;