I think that means insisting on civility in our gatherings. Speaking out both in public and to the people we interact with against what is wrong.
I don't think it is served by trolling peoples internet history to discover if they ever committed any thought crime. Our country will be better off the more MAGAers either age into the grave or get off the stupid train. Keep in mind that many of them are already decent citizens in the way they comport themselves in their lives, in the way they treat the people they interact with. They have just bought into a moronic ideology and will vote to enable further stupidity that will hurt their fellows in a way they would never due if given that straight choice between good and evil directly.
Isolating that person instead of communicating with them is a missed opportunity that serves only to signal our virtue to our fellows. It is a choice to enhance our social status instead of our society. It's positively trumpian and it plays right into his hands by making that person more isolated and thus more vulnerable.
Doing the right thing is hard. Do it anyway.