Only an owner or admin can change permissions

A manager could change what a manager is allowed to do — including granting themselves permissions their shop had switched off. Permissions are now owner-and-admin only, and nobody can change their own role's.

A manager can no longer edit permissions. They can still see the grid, so it is clear what each role may do — the tick boxes are just read-only.
Nobody can change their own role's permissions, including an admin. Your own column is shown locked; ask an owner.
The owner row is locked in the database, not just on screen. An owner always has every permission.