focusing search bar in macos NavigationSplitView

[joprice]

I'm trying to add a search keyboard shortcut to the search bar in a NavigationSplitView, but found an edge case that I think Introspect should be able to help with: The code below works to trigger the search view when the input has no value (isSearching = false), but the shortcut does not work after that to bring focus back to the search bar, since isSearching seems to remain true when the input contains data. I haven't seen a method for associating FocusState with searchable, so I looked for an introspect modified that might help. I found that the searchField modified does not have an implementation for Mac. I ran a capture view hierarchy to see if I could add a local modifier, but wasn't able to figure out where the AppKitSearchField class in the attached screenshot should map to, as I couldn't resolve it. Is it possible to add support to Introspect for this?

.searchable(text: $filter, isPresented: $isSearching, placement: .sidebar)
        .background(
          Button("", action: { isSearching = true })
            .keyboardShortcut("f").hidden()
        )