How to use browser-tabs-lock - 1 common examples

runIframe,
  sha256,
  bufferToBase64UrlEncoded,
  oauthToken,
  openPopup
} from './utils';

import Cache from './cache';
import TransactionManager from './transaction-manager';
import { verify as verifyIdToken } from './jwt';
import { AuthenticationError } from './errors';
import * as ClientStorage from './storage';
import { DEFAULT_POPUP_CONFIG_OPTIONS } from './constants';
import version from './version';

const lock = new Lock();
const GET_TOKEN_SILENTLY_LOCK_KEY = 'auth0.lock.getTokenSilently';

/**
 * Auth0 SDK for Single Page Applications using [Authorization Code Grant Flow with PKCE](https://auth0.com/docs/api-auth/tutorials/authorization-code-grant-pkce).
 */
export default class Auth0Client {
  private cache: Cache;
  private transactionManager: TransactionManager;
  private domainUrl: string;
  private tokenIssuer: string;
  private readonly DEFAULT_SCOPE = 'openid profile email';

  constructor(private options: Auth0ClientOptions) {
    this.cache = new Cache();
    this.transactionManager = new TransactionManager();
    this.domainUrl = `https://${this.options.domain}`;