Orderable folder arrows are not usable

Studio-side

1. create a document type myFolderType extending Folder (or OrderedFolder)
2. create a document type myDocumentType allowed to be created in myFolderType
3. switch to Designer
4. generate forms for myFolderType and myDocumentType
5. edit the myFolderType table results
6. select orderable in the Attributes section

Server-side

1. install nuxeo
2. synch the project
3. create a folder myTestFolder of type myFolderType
4. create 3 documents azerty1, azerty2, azerty3 of type myFolderType
5. observe the arrows being displayed next to each document line instead of being on the same line than the filters.