The Rabbis decreed that we should not fulfill the commandments of shofar, lulav, and megillas Esther in order that we not come to desecrate the Sabbath (i.e. by carrying these religious articles through a public thoroughfare in violation of Sabbath laws). Why did they not prohibit the lighting of Chanukah candles on Friday? The ideal time to light candles is after sunset, and someone might light candles at that time (which is forbidden according to Sabbath law)!

The Genius of Rogatchov answers that, specifically on Friday, the ideal time to light Chanuka candles is from plag hamincha (approximately 1 hour before sunset) until prior to sunset. This is clearly not the case with regard to the commandments of shofar, lulav, and megillas Esther, as their fulfillment is scheduled to be accomplished, specifically, on the Sabbath day.