Neos\Neos\Domain\Service\UserService::removeOwnerFromUsersWorkspaces PHP Method

    protected function removeOwnerFromUsersWorkspaces(User $user)
    {
        /** @var Workspace $workspace */
        foreach ($this->workspaceRepository->findByOwner($user) as $workspace) {
            $workspace->setOwner(null);
            $this->workspaceRepository->update($workspace);
        }
    }