As I said above, although there is no `_U` clash now, that does not exclude that there was a clash in the past, menus change.
As I noted if anyone cares they can check in git history.
Even when a clashing accelerator is removed from a menu it is still not a good idea to reorganise the rest of the menu because users who operate software via the keyboard (by choice or lack of mouse) get to learn these sequences eg `Alt+e f n` for uncomment lines, and are unhappy if they are changed. They get even more unhappy if accelerators are changed for "no reason" just to use the `_U`.