user_admin_menu
Action Hook: Fires before the administration menu loads in the User Admin.
Source: wp-admin/includes/menu.php:145
admin_menu
Action Hook: Fires before the administration menu loads in the admin.
Source: wp-admin/includes/menu.php:155
custom_menu_order
Filter Hook: Filters whether to enable custom ordering of the administration menu.
Source: wp-admin/includes/menu.php:273