AF3 shows no models in Navigator if started without initialized workspace
Problem occurs with current nightly on macOS sierra.
Neither Model Navigator nor Resource Viewer show any content if AF3 is started without an initialized workspace from an earlier version.
New AF3-Projects can be created and also show up in the file system, but they are also not displayed.
(from redmine: issue id 2749, created on 2016-11-24, closed on 2017-01-30)