SwiftUI .keyboardShortcut stops working after entering fullscreen

I am having a fairly specific problem with my keyboard shortcuts for my SwiftUI application. I have a set of buttons in my toolbar that correspond to different actions and keys, but the button that uses just .return as its shortcut doesn't work once I enter fullscreen (press the green button to maximize) and even once I exit fullscreen.

Here is a video showing the behavior: link

As you can see both on the button and in the console in the bottom right, the enter key activates the button until I enter fullscreen. I will put code snippets below showing how I have things set up. This is also my first project in Swift so any general help would be great :)

struct ContentView: View {
    @Binding var document: OutlinerDocument
    
    var body: some View {
        Text("Tree goes here")
            .font(.title)
            .frame(minWidth: 400, idealWidth: 600, maxWidth: .infinity, minHeight: 300, idealHeight: 400, maxHeight: .infinity, alignment: .center)
            .toolbar(content: {
                // main buttons to modify the model
                HStack(alignment: .bottom) {
                    ActionButton(imageName: "text.badge.minus", label: "Delete item(s)", customAction: customAction)
                        .keyboardShortcut(.delete, modifiers: [])
                    ActionButton(imageName: "text.badge.plus", label: "Add item", customAction: customAction)
                        .keyboardShortcut(.return, modifiers: [])
                    ActionButton(imageName: "text.badge.star", label: "Add child", customAction: customAction)
                        .keyboardShortcut(.return, modifiers: [.shift])
                    ActionButton(imageName: "arrow.right.to.line", label: "Indent", customAction: customAction)
                        .keyboardShortcut(.tab, modifiers: [])
                    ActionButton(imageName: "arrow.left.to.line", label: "Outdent", customAction: customAction)
                        .keyboardShortcut(.tab, modifiers: [.shift])
                }
            })
            .focusable()
    }
}

struct ActionButton: View {
    var imageName: String
    var label: String
    var customAction: () -> Void

    var body: some View {
        Button(action: customAction, label: {
            Image(systemName: imageName)
                .font(.title)
        })
        .help(label)
    }
}