toSend, err = m.MarshalMsg(toSend)
		if err != nil {
			gridLogIf(ctx, fmt.Errorf("msg.MarshalMsg: %w", err))
			return
		}
		// Append as byte slices.
		for _, q := range queue {
			toSend = msgp.AppendBytes(toSend, q)
			PutByteBuffer(q)
		}
		queue = queue[:0]
		queueSize = 0

		// Combine writes.
		// Consider avoiding buffer copy.
		err = wsw.writeMessage(&buf, c.side, ws.OpBinary, toSend)