init() {
    this.isSessionStorageSupported = this._isSessionStorage();
    this.addListeners();
    this._restoreData();
    this.sendMessageToParent(this.getTabInfo(), PostMessageEventNamesEnum.LOADED);
    this.timeout = this.setHandshakeExpiry();

    if (this.config.onReady) {
      this.config.onReady();
    }
  }
Invoked on object instantiation unless user pass a key to call it explicitly