who lives on the 50th floor at trump tower
Todd Brassner, an art dealer used to live there
Trump Tower
At around 5:30 p.m. (EDT) on April 7, 2018, a 4-alarm fire broke out in a condominium in the tower's 50th floor, killing a resident and injuring six firefighters; the apartment was almost entirely engulfed in flames by the time the New York City Fire Department (FDNY) arrived. In a Twitter post, Trump attributed the fire's limited damage to the building's design. The sole fatality was 67-year-old Todd Brassner, an art dealer known for his association with Andy Warhol, who had endured debilitating medical problems for several years. 
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Trump Tower [SEP] Incidents
Brassner's apartment, as well as the rest of the residential units in Trump Tower, did not contain sprinklers because the structure had been built before 1999, when the city passed a law requiring sprinklers in residential units; Trump had lobbied against the proposal. The FDNY later announced that the fire had been accidentally caused by power wires that had overheated. The April 2018 fire followed a minor electrical fire at the tower earlier that year, which had injured three people. In July 2020, activists including New York City mayor Bill de Blasio painted the words "Black Lives Matter" in giant letters on Fifth Avenue directly in front of the building.