createChatRoom(convertUserID, inviteUserID, callback) {
		return StdLib.Promises.callbackPromise(['chatID'], callback, true, (resolve, reject) => {
			convertUserID = convertUserID || new SteamID();
			inviteUserID = inviteUserID || new SteamID();

			let msg = ByteBuffer.allocate(53, ByteBuffer.LITTLE_ENDIAN);
			msg.writeUint32(EChatRoomType.MUC); // multi-user chat
			msg.writeUint64(0);
			msg.writeUint64(0);
			msg.writeUint32(EChatPermission.MemberDefault);
			msg.writeUint32(EChatPermission.MemberDefault);
			msg.writeUint32(EChatPermission.EveryoneDefault);
			msg.writeUint32(0);
			msg.writeUint8(EChatFlags.Locked);
			msg.writeUint64(Helpers.steamID(convertUserID).getSteamID64());
			msg.writeUint64(Helpers.steamID(inviteUserID).getSteamID64());
			this._send(EMsg.ClientCreateChat, msg.flip());

			/**
			 * Called when the room is created or a failure occurs. If successful, you will be in the room when this callback fires.
			 * @callback SteamUser~createChatRoomCallback
			 * @param {Error|null} err - The result of the creation request
			 * @param {SteamID} [chatID] - The SteamID of the newly-created room, if successful
			 */
			Helpers.onceTimeout(10000, this, 'chatCreated#' + convertUserID.getSteamID64(), (err, convertUserID, result, chatID) => {
				err = err || Helpers.eresultError(result || EResult.OK);
				if (err) {
					return reject(err);
				} else {
					return resolve({chatID});
				}
			});
		});
	}
Creates a new multi-user chat room
@param {null|SteamID|string} [convertUserID=null] - If the user with the SteamID passed here has a chat window open with us, their window will be converted to the new chat room and they'll join it automatically. If they don't have a window open, they'll get an invite.
@param {null|SteamID|string} [inviteUserID=null] - If specified, the user with the SteamID passed here will get invited to the new room automatically.
@param {SteamUser~createChatRoomCallback} [callback] - Called when the chat is created or a failure occurs.
@return Promise
@deprecated This uses the old-style chat rooms, if you want new chat instead use this.chat