Can't rearrange Folder on ModificationDate

[gp54321]

The index don't exist. Available indexes on a Folder are:
Creator
Date
Description
SearchableText
Subject
Title
Type
UID
allowedRolesAndUsers
cmf_uid
commentators
created
effective
effectiveRange
end
expires
getId
getObjPositionInParent
getRawRelatedItems
id
in_reply_to
is_default_page
is_folderish
meta_type
modified
object_provides
path
portal_type
review_state
sortable_title
start
sync_uid
total_comments

so the supposed index 'ModificationDate' is not available

Changing plone/app/content/browser/contents/__init__.py so:
--- __init__.py.ori	2017-12-25 23:19:33.351624000 +0100
+++ __init__.py	2018-01-17 11:56:01.438211350 +0100
@@ -179,7 +179,6 @@
             'in_response_to',
             'listCreators',
             'meta_type',
-            'modified',
             'portal_type',
             'sync_uid'
         ]
@@ -200,7 +199,7 @@
             'is_folderish': translate(_('Folder'), context=self.request),
             'last_comment_date': translate(_('Last comment date'), context=self.request),  # noqa
             'location': translate(_('Location'), context=self.request),
-            'ModificationDate': translate(_('Last modified'), context=self.request),  # noqa
+            'modified': translate(_('Last modified'), context=self.request),  # noqa
             'review_state': translate(_('Review state'), context=self.request),  # noqa
             'start': translate(_('Start Date'), context=self.request),
             'Subject': translate(_('Tags'), context=self.request),
@@ -246,7 +245,6 @@
             'getRawRelatedItems',
             'in_reply_to',
             'meta_type',
-            'modified',
             'object_provides',
             'portal_type',
             'SearchableText',
@@ -264,7 +262,7 @@
             'expires': translate(_('Expiration date'), context=self.request),
             'id': translate(_('ID'), context=self.request),
             'is_folderish': translate(_('Folder'), context=self.request),
-            'ModificationDate': translate(_('Last modified'), context=self.request),  # noqa
+            'modified': translate(_('Last modified'), context=self.request),  # noqa
             'review_state': translate(_('Review state'), context=self.request),
             'sortable_title': translate(_('Title'), context=self.request),
             'start': translate(_('Start Date'), context=self.request),
@@ -341,7 +339,7 @@
         'is_folderish',
         'last_comment_date',
         'location',
-        'ModificationDate',
+        'modified',
         'path',
         'portal_type',
         'review_state',

makes rearranging a folder for 'Last modified' work successfully