The Copy / Move or rename feature is not supported explicitly yet, the way to use for the moment is to rename outside of SourceTree and use the Add/remove button on the toolbar instead.
I would recommend you to vote on the following feature request and add yourself as watcher so you'll be notified when it gets updated:
Hi team, I’m Avinoam, a product manager on Confluence Cloud, and today I’m really excited to let the Community know that all customers can now try out the new editing experience and see some of the ...
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