Menachem, most jews did not sleep in a sukkah in Europe. The mitteler rebbe had a valid, normal halachik heter not to. The last Lubavitcher rebbe was the one who came up with the mitztayer that you’re not mitztayer that you’re not mitztayer business; and no, there’s no reference to look at tzafnas paneach or other seforim from the rogotchover.
Where is the source for that, and where is the source for not washing for shalosh seudos? It just doesn’t exist. He was mechadesh these things
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