Fix TabBarMinimize and prefersLargeTitle behaviour

Source/Turbo/Visitable/Visitable.swift

@@ -49,11 +49,22 @@ extension Visitable {
 
     func activateVisitableWebView(_ webView: WKWebView) {
         visitableView.activateWebView(webView, forVisitable: self)
+        // Explicitly designate the web view's scroll view as the tracked content
+        // scroll view so behaviour like UINavigationBar.prefersLargeTitles and the
+        // iOS 26 tab bar minimize trigger reliably, without depending on UIKit's
+        // subview-ordering heuristic. `.all` covers the top (nav bar) and bottom
+        // (tab bar) edges.
+        if #available(iOS 15.0, *) {
+            visitableViewController.setContentScrollView(webView.scrollView, for: .all)
+        }
         visitableDidActivateWebView(webView)
     }
 
     func deactivateVisitableWebView() {
         visitableWillDeactivateWebView()
+        if #available(iOS 15.0, *) {
+            visitableViewController.setContentScrollView(nil, for: .all)
+        }
         visitableView.deactivateWebView()
         visitableDidDeactivateWebView()
     }

Source/Turbo/Visitable/VisitableView.swift

@@ -24,7 +24,10 @@ open class VisitableView: UIView {
     open func activateWebView(_ webView: WKWebView, forVisitable visitable: Visitable) {
         self.webView = webView
         self.visitable = visitable
-        addSubview(webView)
+        // iOS 14 fallback: with no explicit contentScrollView, UIKit's heuristic requires
+        // the scrollable view to be the first subview for large-title / tab-bar-minimize
+        // to work. On iOS 15+ this is made robust by setContentScrollView in Visitable.
+        insertSubview(webView, at: 0)
         addFillConstraints(for: webView)
         installRefreshControl()
         showOrHideWebView()

Tests/Turbo/VisitableViewControllerTests.swift

@@ -47,6 +47,50 @@ class VisitableViewControllerTests: XCTestCase {
         XCTAssertEqual(viewController.initialVisitableURL, originalURL)
         XCTAssertEqual(viewController.currentVisitableURL, overriddenURL)
     }
+
+    func test_webview_is_first_child_during_loading() {
+        XCTAssertEqual(viewController.visitableView.subviews.first, viewController.visitableView.activityIndicatorView)
+
+        viewController.visitableView.activateWebView(webView, forVisitable: viewController)
+
+        XCTAssertEqual(viewController.visitableView.subviews.first, webView)
+        XCTAssertEqual(viewController.visitableView.subviews.last, viewController.visitableView.activityIndicatorView)
+    }
+
+    func test_webview_is_first_child_on_restore() {
+        XCTAssertEqual(viewController.visitableView.subviews.first, viewController.visitableView.activityIndicatorView)
+
+        viewController.showVisitableScreenshot()
+        viewController.visitableView.activateWebView(webView, forVisitable: viewController)
+
+        XCTAssertEqual(viewController.visitableView.subviews.count, 3)
+        XCTAssertEqual(viewController.visitableView.subviews.first, viewController.visitableView.webView)
+
+        viewController.hideVisitableScreenshot()
+
+        XCTAssertEqual(viewController.visitableView.subviews.count, 2)
+        XCTAssertEqual(viewController.visitableView.subviews.first, viewController.visitableView.webView)
+    }
+
+    @available(iOS 15.0, *)
+    func test_activating_webview_designates_its_scroll_view_as_content_scroll_view() {
+        XCTAssertNil(viewController.contentScrollView(for: .top))
+
+        viewController.activateVisitableWebView(webView)
+
+        XCTAssertEqual(viewController.contentScrollView(for: .top), webView.scrollView)
+        XCTAssertEqual(viewController.contentScrollView(for: .bottom), webView.scrollView)
+    }
+
+    @available(iOS 15.0, *)
+    func test_deactivating_webview_clears_the_content_scroll_view() {
+        viewController.activateVisitableWebView(webView)
+        XCTAssertEqual(viewController.contentScrollView(for: .top), webView.scrollView)
+
+        viewController.deactivateVisitableWebView()
+
+        XCTAssertNil(viewController.contentScrollView(for: .top))
+    }
 }
 
 final class WebViewSpy: WKWebView {