We haven't considered such component until now since the Microsoft.Win32 OpenFileDialog and SaveFileDialog work pretty good for the needs of the controls in the suite. Also, since the WPF framework allows access to the file system, you can create your own dialog to fit specific needs.
Still, the idea sounds pretty interesting. Do you mind sharing what kind of functionality you would expect from such component? You can also submit a feature request on our Public Portal
where the community can vote for faster implementation of the idea.
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