Be able to simply remove or configure some menu entries, without the need to create a custom skin, know CSS or disable extension points.
I am creating this issue since I see this recurrent request with our users, one example: https://forum.xwiki.org/t/how-to-remove-view-source-children
Users want to control exactly what entries are displayed, and in some case certain entries to appear just for some users. Currently it's easy for us to ADD new entries in the menus, but almost impossible to REMOVE / HIDE entries.
I've linked some related technical issues to this use case issue, since some menu entries come from templates, other from extension points, etc.