Referencing High Only During Market Hours

Hey everyone! I am using a chart study on the 1 minute chart (that also shows extended hours trading). I am using the code below to track the highest high but I would like it not to reference the extended hours high.

I’ve tried a couple different solutions but am running into problems. I am sure I’m missing something obvious. Thank you!
*I have also tried to incorporate the “mkth” variable into the equation but it appears that this randomly causes nothing to be plotted. Example:

rec trackHigh = if mkth ==0 then 0 else (if newDay then high else if high > trackHigh[1] then high else trackHigh[1]);

def mkth = GetTime() > RegularTradingStart(GetYYYYMMDD()) and GetTime() < RegularTradingEnd(GetYYYYMMDD());
def newDay = GetDay() <> GetDay()[1];
rec trackHigh = if newDay then high else if high > trackHigh[1] then high else trackHigh[1];