As the team was completing a report on its findings last summer, Mr. Murray found himself staring down a newsroom revolt. Soon after the killing of George Floyd, staff members created a private Slack channel called “Newsroomies,” where they discussed how The Journal, in their view, was behind on major stories of the day, including the social justice movement growing in the aftermath of Mr. Floyd’s death. Participants also complained that The Journal’s digital presence was not robust enough, and that its conservative opinion department had published essays that did not meet standards applied to the reporting staff. The tensions and challenges are similar to what leaders of other news organizations, including The Times, have heard from their staffs.