...
Diagrams that you create will be stored as an attachment to the original Confluence wiki page. Each time you save your diagram in the Gliffy Editor, a new version of your diagram will be created and attached to your Confluence page. The diagram will retain the same name, so you'll have a complete version history of all changes. However, do not edit the attachment by hand or you will destroy the diagram and have to revert to a previous version.
...