Outbound Tag Not Set Due to Missing Options in Contact.toString() (Registrator.js:39)

[DarkHorse109707]

Hello Dear.
In UA.js (line 922), there is a contact object, and its toString() method requires options to enable the outbound tag.
However, I noticed that in Registrator.js (line 39), this._ua.contact.toString() is called without any options.
I need to add the "ob" parameter to the contact, and I would appreciate your advice on how best to do this.

Thank you!