Someone who I didn't think was progressive but who I assumed was reasonable went full-on "if the right-wing takes over France it's because the ungrateful immigrants tried to destroy the country" and welp.
you know i'm not, like, a scholar of french politics or whatever but hasn't there been a pretty long-running series of tension over immigration for nearly three decades or so
I am almost certain this is who the OP had in mind, or at least it's the first thing I thought of.
People need to get better at recognizing charlatans or "liberals" who will bolt for the right-wing grievance money at the first opportunity.
modern version of COINTELPRO of leftists, first for antifa & progressives, then for more centrist Democrats
makes sense for fascists to operate this way