Editable Elements in XML Schema

Sep 22, 2015 at 5:41 PM
Edited Sep 22, 2015 at 5:43 PM
Is it possible to edit the definition within the XML Documents collection within content types of a site collection within SharePoint Manager 2013 version 2.0?

Specifically I'm trying to edit the list of allowed content types for a document set. Is there another method of editing? I've tried adding to the list directly in the XML schema and editing within the document collection. Neither appear to be read only but after a save all the changes still disappear after a refresh. Any ideas? A different approach?