Hi, I'm implementing a swiping tab view using SwiftUI's PageTabViewStyle() tabView style, similar to, say, Reddit mobile. On the top are all the tab names which turn blue, and right under a small Capsule() which moves to the selected tab. I'm having difficulty making the capsule move using matchedGeometryEffect() when the user has gone to a new tab, however.

// The parent view
@State private var selectedTab: Category = .all
// [...]
VStack(spacing: 0) {
    HistoryNavigationBar(selectedTab: $selectedTab)
    TabView(selection: $selectedTab) {
        ForEach(Category.allCases, id: \.self) { category in
            HistoryList(category: category)
        }
    }
    .tabViewStyle(PageTabViewStyle(indexDisplayMode: .never))
}

With the important parts of HistoryNavigationBar being:

@Namespace private var animation
// [...]
ForEach(History.Category.allCases, id: \.self) { category in
    VStack(alignment: .leading, spacing: 5) {
        Button(action: { selectedTab = category }) {
            Text(category.rawValue.capitalized)
                .foregroundColor(selectedTab == category ? .blue : .gray)
        }
        Capsule()
            .frame(width: 20, height: 2)
            .foregroundColor(selectedTab == category ? .blue : .clear)
    }
}

How should I implement matchedGeometryEffect() to get the desired effect of the capsule moving every time the tab is changed? I tried all sorts of combinations with matchedGeometryEffect() (putting it after the capsule, putting the capsule in an if-statement, etc.), but to no success – whenever I swipe between tabs, or click on one of the tab names, the capsule just jumps to that tab.