silverstripe/silverstripe-framework — pull request #2106 by g4b0 (2013-06-17 07:43:53+00:00)
Title: BUGFIX: added many_many relationship hidden inupt

Without this hidden input the file uploading will not work for many_many relationship. File is uploaded, database record in table File is created, but the record in many_many join table is not created due to the lack of information about the file ID.