I am trying to follow along in the SwiftUI containers session and I am getting the error Cannot find type Content in scope when using a line like: @ViewBuilder var content: Content I am using Xcode 16 beta and the project is set for iOS 18 as a minimum. Is there more I need to do?

I am getting this error in my preview: CompileDylibError: Failed to build ContentView.swift Compiling failed: main actor-isolated let 'previewContainer' can not be referenced from a non-isolated context I don't know enough about @MainActor to figure this out.