Removing-background-from-DrawText-renderings

CODE:
using WealthLab.Backtest;
using System;
using WealthLab.Core;
using WealthLab.Data;
using WealthLab.Indicators;
using System.Collections.Generic;

namespace WealthScript6 
{
    public class MyStrategy : UserStrategyBase
    {
        public override void Initialize(BarHistory bars)
        {
         MACD macd = MACD.Series(bars.Close, 12, 26);
         EMA Avg = EMA.Series(macd, 9);
         PlotIndicator(macd);
         PlotIndicator(Avg);
         
         double L = macd.LastValue;
         WLColor labelColor = L > Avg.LastValue && L > 0 ? WLColor.LimeGreen : L < Avg.LastValue && L < 0 ? WLColor.Red : WLColor.Yellow;
         SetTextDrawingOptions(labelColor, WLColor.Black, 1);
         string txt = "MACD = " + macd.LastValue.ToString("N2");
         DrawHeaderText(txt, WLColor.Black, 14, macd.PaneTag);
         
         int idx = bars.Count - 20;
         L = macd[idx];
         txt = "MACD = " + L.ToString("N2");
         labelColor = L > Avg[idx] && L > 0 ? WLColor.LimeGreen : L < Avg[idx] && L < 0 ? WLColor.Red : WLColor.Yellow;
         SetTextDrawingOptions(labelColor, WLColor.Black, 1);
         DrawText(txt, idx, bars.High[idx], WLColor.Black, 10, "Price", true);    
         
         
         // reset the background for subsequent calls to text 
         SetTextDrawingOptions(WLColor.Transparent, WLColor.Transparent, 0);
        }

        public override void Execute(BarHistory bars, int idx)
        {
        }
    }
}