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I am working on a test app utilizing UISplitViewController. I search for ContainerView and drag it onto the Detail View. Then I search for an ImageView and drag it onto the Detail View. The ContainerView disappears and is replaced by the ImageView. I've deleted and recreated several times, and have also rebooted and it doesn't change how it works. Have you experienced this or is there a fix? I am using Xcode 13.4, and Monterey 12.4.