“Verification was meant to authenticate identity and voice but it is interpreted as an endorsement or importance,” the company said on Twitter. “We have created this confusion.”

Twitter originally began verifying accounts to give high-profile individuals — celebrities, politicians, journalists and others — a way to distinguish themselves from impersonators. The blue check mark has since become something of a badge of honor, signaling that someone had reached a certain level of importance.

“It’s recognition. It’s a simple as that,” Richard Spencer, a white supremacist who was verified by Twitter in 2016, said in an interview. “The blue check mark is useful.”

The white nationalist movement has flourished on Twitter, but Mr. Spencer said the platform had been behaving erratically toward his community lately.

“It seems to be non-algorithmic now,” he said. “It seems like there’s one person who doesn’t like this tweet or that account one day, and it seems like a judgment. It’s incoherent.”

Mr. Kessler’s account — with the handle @TheMadDimension — remains verified. Late Wednesday, he responded to the uproar with a tweet wondering if it was still O.K. to be white, and included a poll for people to answer. As of Thursday afternoon, he had gotten nearly 50,000 responses.