As the crisis escalated, Ms. Rose resigned from Artshack Brooklyn, a nonprofit ceramics studio she helped run in nearby Bedford-Stuyvesant; a statement appeared on Artshack’s website denouncing the display. Yet the crisis was not defused, and soon activists, parents and local elected officials turned up at Artshack, demanding it take responsibility for Ms. Rose’s paper dolls. The alternative — as the crowd chanted — was to leave the neighborhood.

Image Artshack, in Bedford-Stuyvesant. Credit... Artshack

“I really grappled with this,” said Steven D. Clunis, a graphic designer and the father of two girls, one a student at P.S. 11. In today’s climate, it was sadly not surprising to see such imagery dragged out from the past, he said. “But I didn’t want to have that conversation with a first grader.” Considering his children, Mr. Clunis, who is black, said, “I couldn’t do nothing.” He and his family joined protesters.

Those at Artshack — which had absolutely nothing to do with the Halloween decorations — nonetheless understood the need to be part of the solution. “There was a lot of hurt and anger, and rightfully so,” said McKendree Key, the co-founder and director of the studio, who is white. “No one is saying this is crazy. Everyone is saying, yeah — we have to answer for this.”

Ms. Key called a community meeting, and on Nov. 2, around 100 people gathered at Bedford Academy in Bedford-Stuyvesant, including Mr. Foy and Letitia James, New York’s attorney general and a Bedford-Stuyvesant resident herself.

The result could have been a conversation that dwelled on the Halloween decorations. Instead what ensued was an unusually frank discussion, by all accounts, about racism and the neighborhood — not racism in the sense of overt prejudice, but in the sense that while pouring money into homes and businesses, Mr. Foy said, some newcomers to this part of Brooklyn have behaved not as if they are adding to an already-rich culture, but have supplanted it, as if there had been nothing there before at all.

In this sense, said Mr. Foy, they are “operating from a place of white supremacy.”

Summing up what had been days of emotional conversations online, in churches and homes, Ms. James said: “There are people in this community, primarily of African ancestry, who feel a sense of loss. They don’t know this community anymore.”

In 2018, the number of new businesses in Bedford-Stuyvesant had increased by 152 percent since 2000, the fastest rate of growth of any of New York City’s 55 census-defined neighborhoods. In the same period, the black population of the neighborhood dropped from three-quarters to less than half, according to census data.