Thank you for your patience on this issue.
We are pleased to announce that the new Edit Files experience is here. From Confluence 6.11 (release notes). Now, you can edit any file attached to a Confluence page using your preferred desktop application, then save the file back to Confluence automatically. The new Atlassian Companion app works across Windows and Mac operating systems with any of our supported Browsers.
Victoria Li | Product Manager - Confluence Server