The Owner role is only available at the group or personal namespace level (and for instance administrators) and is inherited by its projects. While Maintainer is the highest project-level role, some actions can only be performed by a personal namespace or group owner, or an instance administrator, who receives all permissions.What is the difference between a personal namespace owner and maintainer?
Personal namespace owners have the same permissions as an Owner, but are displayed with the Maintainer role on projects created in their personal namespace. For more information, see projects members documentation .What is the difference between master and maintainer in GitLab?
Note: In GitLab 11.0, the Master role was renamed to Maintainer. While Maintainer is the highest project-level role, some actions can only be performed by a personal namespace or group owner. The following table depicts the various user permission levels in a project.Can a maintainer change project features visibility level?
A Maintainer can’t change project features visibility level if project visibility is set to private. Attached design files are moved together with the issue even if the user doesn’t have the Developer role. Guest users can only set metadata (for example, labels, assignees, or milestones) when creating an issue.