diff --git a/moli-benchmark/wpt-cross-current/failed-cases.txt b/moli-benchmark/wpt-cross-current/failed-cases.txt
index a1afaf4707..d6304108f0 100644
--- a/moli-benchmark/wpt-cross-current/failed-cases.txt
+++ b/moli-benchmark/wpt-cross-current/failed-cases.txt
@@ -2722,9 +2722,6 @@ html/browsers/browsing-the-web/navigating-across-documents/replace-before-load/l
 html/browsers/browsing-the-web/navigating-across-documents/replace-before-load/location-setter-during-load.html
 html/browsers/browsing-the-web/navigating-across-documents/replace-before-load/location-setter-during-pageshow.html
 html/browsers/browsing-the-web/navigating-across-documents/replace-before-load/location-setter.html
-html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-cross-document-nav.html
-html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-cross-document-traversal.html
-html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-same-document-nav.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-same-document-traversal.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-traversal-cross-document-traversal.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-traversal-same-document-traversal.html
diff --git a/moli-benchmark/wpt-cross-current/passed-cases.txt b/moli-benchmark/wpt-cross-current/passed-cases.txt
index 918ecfa879..7f4b9b2609 100644
--- a/moli-benchmark/wpt-cross-current/passed-cases.txt
+++ b/moli-benchmark/wpt-cross-current/passed-cases.txt
@@ -5293,6 +5293,9 @@ html/browsers/browsing-the-web/navigating-across-documents/source/navigate-child
 html/browsers/browsing-the-web/navigating-across-documents/source/navigate-child-function.html
 html/browsers/browsing-the-web/navigating-across-documents/source/navigate-child-src-about-blank.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/anchor-fragment-history-back-on-click.html
+html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-cross-document-nav.html
+html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-cross-document-traversal.html
+html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-same-document-nav.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-nav-stop.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-traversal-same-document-nav.html
 html/browsers/browsing-the-web/overlapping-navigations-and-traversals/cross-document-traversal-stop.html
diff --git a/moli-core/tests/history_child.rs b/moli-core/tests/history_child.rs
index 1269670ecf..82a5ef8ec5 100644
--- a/moli-core/tests/history_child.rs
+++ b/moli-core/tests/history_child.rs
@@ -334,7 +334,7 @@ async fn assert_child_location_navigation_stays_window_local(
         page.serialize_html_async()
             .await
             .unwrap()
-            .contains(&format!("data-child-current-entry-url=\"{}\"", final_url)),
+            .contains(&format!("data-child-current-entry-url=\"{}\"", initial_url)),
         "{}",
         page.serialize_html_async().await.unwrap()
     );
@@ -342,7 +342,7 @@ async fn assert_child_location_navigation_stays_window_local(
         page.serialize_html_async()
             .await
             .unwrap()
-            .contains(&format!("data-child-location-href=\"{}\"", final_url)),
+            .contains(&format!("data-child-location-href=\"{}\"", initial_url)),
         "{}",
         page.serialize_html_async().await.unwrap()
     );
@@ -352,7 +352,7 @@ async fn assert_child_location_navigation_stays_window_local(
             .unwrap()
             .contains(&format!(
                 "data-child-document-location-immediate=\"{}\"",
-                final_url
+                initial_url
             )),
         "{}",
         page.serialize_html_async().await.unwrap()
@@ -438,7 +438,7 @@ async fn assert_child_location_navigation_stays_window_local(
         page.serialize_html_async()
             .await
             .unwrap()
-            .contains("data-child-location-target-pending-microtask=\"true\"")
+            .contains("data-child-location-target-pending-microtask=\"false\"")
     );
     assert!(
         page.serialize_html_async()
@@ -446,7 +446,7 @@ async fn assert_child_location_navigation_stays_window_local(
             .unwrap()
             .contains(&format!(
                 "data-child-document-location-pending-microtask=\"{}\"",
-                final_url
+                initial_url
             )),
         "{}",
         page.serialize_html_async().await.unwrap()
@@ -526,6 +526,15 @@ async fn assert_child_location_navigation_stays_window_local(
             .unwrap()
             .contains("data-child-document-text-after-load=\"delayed\"")
     );
+    assert_eq!(
+        evaluated_string(
+            page.evaluate_runtime_expression_async(
+                "document.getElementById('child').contentWindow.navigation.currentEntry.url",
+            )
+            .await?
+        ),
+        Some(final_url)
+    );
 
     Ok(())
 }
@@ -700,14 +709,14 @@ async fn assert_child_location_component_keeps_committed_document_until_load(
         "data-document-default-view-same-immediate=\"true\"",
         "data-default-view-document-same-immediate=\"true\"",
         "data-child-document-still-committed-immediate=\"true\"",
-        "data-child-location-target-immediate=\"true\"",
+        "data-child-location-target-immediate=\"false\"",
         "data-window-same-pending-microtask=\"true\"",
         "data-document-same-pending-microtask=\"true\"",
         "data-window-document-same-pending-microtask=\"true\"",
         "data-document-default-view-same-pending-microtask=\"true\"",
         "data-default-view-document-same-pending-microtask=\"true\"",
         "data-child-document-still-committed-pending-microtask=\"true\"",
-        "data-child-location-target-pending-microtask=\"true\"",
+        "data-child-location-target-pending-microtask=\"false\"",
         "data-document-replaced-after-load=\"true\"",
     ] {
         assert!(html.contains(attr), "{attr}\n{html}");
@@ -738,8 +747,11 @@ async fn assert_child_location_component_keeps_committed_document_until_load(
         assert_html_contains_attr(&html, "data-child-document-text-after-load", final_text);
     }
     for attr in [
-        ("data-child-location-immediate", final_url),
-        ("data-child-location-pending-microtask", final_url),
+        ("data-child-location-immediate", initial_url.as_str()),
+        (
+            "data-child-location-pending-microtask",
+            initial_url.as_str(),
+        ),
         ("data-child-location-after-load", final_url),
         ("data-child-document-url-immediate", &initial_url),
         ("data-child-document-url-pending-microtask", &initial_url),
@@ -749,19 +761,19 @@ async fn assert_child_location_component_keeps_committed_document_until_load(
     if !final_is_cross_origin {
         assert_html_contains_attr(&html, "data-child-document-url-after-load", final_url);
     }
-    for attr in [
-        "data-child-pathname-immediate",
-        "data-child-pathname-pending-microtask",
-        "data-child-pathname-after-load",
+    let initial_pathname = Url::parse(&initial_url)?.path().to_owned();
+    for (attr, value) in [
+        ("data-child-pathname-immediate", initial_pathname.as_str()),
+        (
+            "data-child-pathname-pending-microtask",
+            initial_pathname.as_str(),
+        ),
+        ("data-child-pathname-after-load", final_pathname),
+        ("data-child-search-immediate", ""),
+        ("data-child-search-pending-microtask", ""),
+        ("data-child-search-after-load", final_search),
     ] {
-        assert_html_contains_attr(&html, attr, final_pathname);
-    }
-    for attr in [
-        "data-child-search-immediate",
-        "data-child-search-pending-microtask",
-        "data-child-search-after-load",
-    ] {
-        assert_html_contains_attr(&html, attr, final_search);
+        assert_html_contains_attr(&html, attr, value);
     }
 
     Ok(())
diff --git a/moli-renderer-v8/src/context_bootstrap/location_navigation.rs b/moli-renderer-v8/src/context_bootstrap/location_navigation.rs
index 00c3b1d86d..65bbf8ba51 100644
--- a/moli-renderer-v8/src/context_bootstrap/location_navigation.rs
+++ b/moli-renderer-v8/src/context_bootstrap/location_navigation.rs
@@ -23,8 +23,8 @@ use super::navigation_lifecycle::{
     settle_navigation_transition_finished_local,
 };
 use super::navigation_mutation::{
-    apply_local_window_location_navigation, apply_navigation_navigate_same_document,
-    sync_local_document_front_from_window, update_navigation_current_entry_for_same_document,
+    apply_navigation_navigate_same_document, sync_local_document_front_from_window,
+    update_navigation_current_entry_for_same_document,
 };
 use super::navigation_reload::{NavigationReloadAdmission, navigation_reload_admission};
 use super::navigation_result::{
@@ -670,29 +670,34 @@ fn navigate_location_object_with_source_element_and_child_navigate_event<'s>(
         {
             return;
         }
-        if !is_javascript_url {
-            sync_location_object(scope, location, resolved.as_str());
-            apply_local_window_location_navigation(scope, owner, &resolved, kind);
-        }
         if let Some(host_ptr) = host_ptr {
             let host = unsafe { &mut *host_ptr };
             let initiator_url =
                 explicit_initiator_url.or_else(|| location_navigation_initiator_url(scope, host));
-            if matches!(kind, LocationNavigationKind::Assign) && !is_javascript_url {
-                host.mark_child_browsing_context_top_level_history_increment(handle);
-            }
-            if matches!(kind, LocationNavigationKind::Reload) {
-                host.queue_child_browsing_context_reload_from_existing_seed(
-                    handle,
-                    resolved.as_str(),
-                    initiator_url,
-                );
-            } else {
+            if is_javascript_url {
                 host.queue_child_browsing_context_navigation_without_seed_update(
                     handle,
                     resolved.as_str(),
                     initiator_url,
                 );
+            } else {
+                // A cross-document navigation only prepares the next history
+                // entry. The old Document's Location, history state and entry
+                // identity remain visible until the replacement commits.
+                let entry_seed = if matches!(kind, LocationNavigationKind::Reload) {
+                    history_entry_seed_for_reload(scope, owner)
+                } else {
+                    history_entry_seed_for_cross_document_location(scope, owner, &resolved, kind)
+                };
+                if let Some(entry_seed) = entry_seed {
+                    host.queue_deferred_child_browsing_context_navigation_from_entry_seed(
+                        handle,
+                        resolved.as_str(),
+                        entry_seed,
+                        matches!(kind, LocationNavigationKind::Assign),
+                        initiator_url,
+                    );
+                }
             }
         }
         return;
diff --git a/moli-renderer-v8/src/context_bootstrap/navigation_cancellation.rs b/moli-renderer-v8/src/context_bootstrap/navigation_cancellation.rs
index 7726c393df..622526fe71 100644
--- a/moli-renderer-v8/src/context_bootstrap/navigation_cancellation.rs
+++ b/moli-renderer-v8/src/context_bootstrap/navigation_cancellation.rs
@@ -10,7 +10,7 @@ use super::{
         cancel_pending_same_document_navigation_finishes_including_reentrant,
     },
     navigation_window::{
-        runtime_window_is_global, runtime_window_owner, window_navigation_for_holder,
+        runtime_window_dispatch_scope, runtime_window_owner, window_navigation_for_holder,
     },
 };
 use crate::util::context_host_ptr_from_global_bridge;
@@ -29,9 +29,24 @@ pub(crate) fn inform_about_canceled_navigation_for_window<'s>(
     cancel_pending_precommit_history_traversal(scope, navigation);
     cancel_pending_precommit_same_document_navigation_for_window_stop(scope, navigation);
     cancel_pending_same_document_navigation_finishes_including_reentrant(scope, navigation);
-    if runtime_window_is_global(scope, owner)
-        && let Some(host_ptr) = context_host_ptr_from_global_bridge(scope)
-    {
-        unsafe { &mut *host_ptr }.clear_pending_location_navigation();
+    clear_pending_cross_document_navigation_for_window(scope, owner);
+}
+
+pub(super) fn clear_pending_cross_document_navigation_for_window<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    window: v8::Local<'s, v8::Object>,
+) {
+    let Some(host_ptr) = context_host_ptr_from_global_bridge(scope) else {
+        return;
+    };
+    let host = unsafe { &mut *host_ptr };
+    match runtime_window_dispatch_scope(scope, window) {
+        Some(crate::native_bridge::OwnerDispatchScope::Top) => {
+            host.clear_pending_location_navigation();
+        }
+        Some(crate::native_bridge::OwnerDispatchScope::Child(handle)) => {
+            host.cancel_pending_child_browsing_context_navigation(handle);
+        }
+        _ => {}
     }
 }
diff --git a/moli-renderer-v8/src/context_bootstrap/navigation_cross_document.rs b/moli-renderer-v8/src/context_bootstrap/navigation_cross_document.rs
index 61f09550c7..fbde6b4251 100644
--- a/moli-renderer-v8/src/context_bootstrap/navigation_cross_document.rs
+++ b/moli-renderer-v8/src/context_bootstrap/navigation_cross_document.rs
@@ -114,8 +114,8 @@ pub(super) fn handle_navigation_navigate_cross_document<'s>(
         next_url.as_str(),
         entry_seed,
         matches!(mutation, NavigationHistoryMutation::Push),
+        None,
     );
-    host.sync_existing_child_browsing_context_window_state(scope, child_handle);
     navigation_signal
         .map(|(navigation, signal)| {
             navigation_cross_document_pending_result(scope, navigation, signal, next_url.as_str())
diff --git a/moli-renderer-v8/src/context_bootstrap/navigation_result.rs b/moli-renderer-v8/src/context_bootstrap/navigation_result.rs
index 261fe3580f..192c714d2d 100644
--- a/moli-renderer-v8/src/context_bootstrap/navigation_result.rs
+++ b/moli-renderer-v8/src/context_bootstrap/navigation_result.rs
@@ -352,6 +352,10 @@ pub(super) fn cancel_active_cross_document_navigation<'s>(
         v8::Boolean::new(scope, false).into(),
     );
     clear_active_cross_document_navigation(scope, navigation);
+    let owner = super::navigation_window::runtime_window_owner(scope, navigation);
+    super::navigation_cancellation::clear_pending_cross_document_navigation_for_window(
+        scope, owner,
+    );
     let error = navigation_dom_exception(scope, "Navigation was canceled", "AbortError");
     if let Some(host_ptr) = context_host_ptr_from_global_bridge(scope) {
         let host = unsafe { &mut *host_ptr };
@@ -360,7 +364,6 @@ pub(super) fn cancel_active_cross_document_navigation<'s>(
         {
             host.abort_signal(scope, signal, error);
         }
-        host.clear_pending_location_navigation();
     }
     finish_navigation_error_events(scope, navigation, error, &href);
     let receiver = v8::undefined(scope).into();
diff --git a/moli-renderer-v8/src/context_bootstrap/navigation_traversal_execution.rs b/moli-renderer-v8/src/context_bootstrap/navigation_traversal_execution.rs
index db17dd07f2..3045d9e480 100644
--- a/moli-renderer-v8/src/context_bootstrap/navigation_traversal_execution.rs
+++ b/moli-renderer-v8/src/context_bootstrap/navigation_traversal_execution.rs
@@ -533,5 +533,6 @@ fn queue_child_cross_document_traversal(
         target_url,
         seed,
         false,
+        None,
     );
 }
diff --git a/moli-renderer-v8/src/context_bootstrap/window_runtime/dialogs.rs b/moli-renderer-v8/src/context_bootstrap/window_runtime/dialogs.rs
index 3bc1c62a29..21e756c566 100644
--- a/moli-renderer-v8/src/context_bootstrap/window_runtime/dialogs.rs
+++ b/moli-renderer-v8/src/context_bootstrap/window_runtime/dialogs.rs
@@ -107,6 +107,23 @@ pub(crate) fn window_stop_callback<'s>(
     args: v8::FunctionCallbackArguments<'s>,
     _rv: v8::ReturnValue<'_, v8::Value>,
 ) {
+    if !crate::context_bootstrap::is_window_receiver(scope, args.this()) {
+        webidl::throw_type_error(scope, "Window.stop called on incompatible receiver.");
+        return;
+    }
+    let owner = super::super::navigation_window::runtime_window_owner(scope, args.this());
+    if super::super::navigation_window::navigation_unload_event_active(scope, owner) {
+        return;
+    }
+    if let Some(crate::native_bridge::OwnerDispatchScope::Child(handle)) =
+        super::super::navigation_window::runtime_window_dispatch_scope(scope, owner)
+        && let Some(host_ptr) = context_host_ptr_from_global_bridge(scope)
+        && unsafe { &*host_ptr }.child_browsing_context_has_pending_cross_document_traversal(handle)
+    {
+        // Unlike an ordinary navigation, session history traversal is not
+        // canceled by Window.stop().
+        return;
+    }
     inform_about_canceled_navigation_for_window(scope, args.this());
 }
 
diff --git a/moli-renderer-v8/src/native_bridge/context_host/child_frame_navigation/commands.rs b/moli-renderer-v8/src/native_bridge/context_host/child_frame_navigation/commands.rs
index 88a98cd990..787071861a 100644
--- a/moli-renderer-v8/src/native_bridge/context_host/child_frame_navigation/commands.rs
+++ b/moli-renderer-v8/src/native_bridge/context_host/child_frame_navigation/commands.rs
@@ -105,6 +105,7 @@ impl JsContextHost {
         resolved_url: &str,
         entry_seed: NavigationHistoryEntrySeed,
         increments_joint_history: bool,
+        initiator_url: Option<Url>,
     ) -> bool {
         if !self.child_browsing_contexts.contains_key(&handle) {
             return false;
@@ -112,6 +113,10 @@ impl JsContextHost {
         let Some(url) = Url::parse(resolved_url).ok() else {
             return false;
         };
+        self.reject_replaced_service_worker_child_client_navigation(
+            handle,
+            "The navigation was canceled.".to_owned(),
+        );
         if let Some(entry) = self.child_browsing_contexts.get_mut(&handle) {
             entry.replace_navigation_entry_seed_and_clear_pending_history_increment(entry_seed);
             if increments_joint_history {
@@ -121,14 +126,15 @@ impl JsContextHost {
         if self
             .set_child_browsing_context_pending_navigation(
                 handle,
-                ChildBrowsingContextBootstrap::Url(url),
-                None,
+                ChildBrowsingContextBootstrap::Url(url.clone()),
+                initiator_url,
                 false,
             )
             .is_none()
         {
             return false;
         }
+        self.register_reserved_service_worker_child_client_for_navigation(handle, &url);
         self.queue_child_browsing_context_navigation_commit(handle)
     }
 
@@ -191,24 +197,49 @@ impl JsContextHost {
         self.queue_child_browsing_context_navigation_commit(handle)
     }
 
-    pub(crate) fn mark_child_browsing_context_top_level_history_increment(
-        &mut self,
+    pub(crate) fn child_browsing_context_has_pending_cross_document_traversal(
+        &self,
         handle: DomHandle,
-    ) {
-        if let Some(entry) = self.child_browsing_contexts.get_mut(&handle) {
-            entry.mark_pending_top_level_history_length_increment();
-        }
-    }
-
-    pub(crate) fn queue_child_browsing_context_reload_from_existing_seed(
-        &mut self,
-        handle: DomHandle,
-        resolved_url: &str,
-        initiator_url: Option<Url>,
     ) -> bool {
-        let Some(url) = Url::parse(resolved_url).ok() else {
+        let Some(entry) = self.child_browsing_contexts.get(&handle) else {
             return false;
         };
-        self.queue_child_browsing_context_navigation_to_url(handle, &url, initiator_url)
+        if !entry.has_pending_navigation_or_document_load() {
+            return false;
+        }
+        let pending = entry.navigation_entry_seed();
+        // The pending activation describes the destination, not the active
+        // Document's last navigation. A traversal must also change position.
+        pending.current_index != entry.committed_navigation_entry_seed().current_index
+            && pending
+                .activation
+                .as_ref()
+                .and_then(|activation| activation.navigation_type.as_deref())
+                == Some("traverse")
+    }
+
+    pub(crate) fn cancel_pending_child_browsing_context_navigation(&mut self, handle: DomHandle) {
+        let Some(entry) = self.child_browsing_contexts.get_mut(&handle) else {
+            return;
+        };
+        if !entry.has_pending_navigation_or_document_load() {
+            return;
+        }
+        entry.clear_pending_navigation();
+        entry.clear_pending_top_level_history_length_increment();
+        entry.restore_navigation_entry_seed_from_committed();
+        self.retire_current_child_navigation_commit_task(handle);
+        self.clear_pending_form_submission_child_target(handle);
+        self.reject_replaced_service_worker_child_client_navigation(
+            handle,
+            "The navigation was canceled.".to_owned(),
+        );
+        if let Some(navigation_load) = self.current_child_navigation_load(handle) {
+            let _ =
+                self.finish_child_frame_navigation_without_load_dispatch(handle, navigation_load);
+        }
+        // Removing the request's owner also makes an already-arriving network
+        // completion stale; it must never install a Document after cancellation.
+        self.clear_pending_child_document_loads_for_handle(handle);
     }
 }
diff --git a/moli-renderer-v8/src/script_vm/tests/browser_api/navigation.rs b/moli-renderer-v8/src/script_vm/tests/browser_api/navigation.rs
index 759062269d..781a433682 100644
--- a/moli-renderer-v8/src/script_vm/tests/browser_api/navigation.rs
+++ b/moli-renderer-v8/src/script_vm/tests/browser_api/navigation.rs
@@ -3467,6 +3467,275 @@ async fn same_document_navigation_precommit_added_handler_delays_finished() {
 
     assert_eq!(after_timeout, "handler|added|finished");
 }
+#[tokio::test]
+async fn window_stop_cancels_child_location_navigation_without_committing_history() {
+    for action in [
+        "child.location.search = '?blocked'",
+        "child.location.assign('/blocked')",
+        "child.location.replace('/blocked')",
+        "child.location.reload()",
+        "const result = child.navigation.navigate('/blocked'); result.committed.catch(() => {}); result.finished.catch(() => {})",
+    ] {
+        let server = StaticHttpServer::spawn(3).await;
+        let parent_url = server.url_for_host("window-stop.test", "/page.html");
+        let loader = static_http_loader([server.resolve_entry("window-stop.test")]);
+        let mut vm =
+            new_storage_page_task_executor_test_vm_with_loader(parent_url.as_str(), &loader);
+        vm.eval(
+            r#"
+globalThis.__stopFrame = document.createElement('iframe');
+globalThis.__stopLoads = 0;
+__stopFrame.onload = () => ++__stopLoads;
+__stopFrame.src = '/child.html';
+(document.body || document.documentElement || document).appendChild(__stopFrame);
+"#,
+        )
+        .expect("window.stop child setup should evaluate");
+        advance_page_task_executor_until_eval_equals(
+            &mut vm,
+            &loader,
+            "String(__stopLoads)",
+            "1",
+            "initial child should load before the canceled navigation",
+        )
+        .await;
+
+        let snapshot = vm
+            .eval(&format!(
+                r#"
+(() => {{
+  globalThis.__stopSibling = document.createElement('iframe');
+  globalThis.__stopSiblingLoaded = false;
+  __stopSibling.onload = () => {{ __stopSiblingLoaded = true; }};
+  __stopSibling.src = '/sibling.html';
+  (document.body || document.documentElement || document).appendChild(__stopSibling);
+  const child = __stopFrame.contentWindow;
+  child.history.replaceState({{ retained: true }}, '', '#original');
+  const documentBefore = child.document;
+  const entryBefore = child.navigation.currentEntry;
+  const lengthBefore = child.history.length;
+  const hrefBefore = child.location.href;
+  const changes = [];
+  child.navigation.oncurrententrychange = () => changes.push('change');
+  globalThis.__stopSnapshot = () => [
+    child.document === documentBefore,
+    child.location.href === hrefBefore,
+    child.document.URL === hrefBefore,
+    child.navigation.currentEntry === entryBefore,
+    child.history.length === lengthBefore,
+    child.history.state?.retained === true,
+    changes.length,
+    __stopLoads
+  ].join('|');
+  {action};
+  const beforeStop = __stopSnapshot();
+  child.stop();
+  child.stop();
+  return beforeStop + ';' + __stopSnapshot();
+}})()
+"#,
+            ))
+            .expect("stopping a child navigation should evaluate");
+        const UNCHANGED: &str = "true|true|true|true|true|true|0|1";
+        assert_eq!(snapshot, format!("{UNCHANGED};{UNCHANGED}"), "{action}");
+
+        advance_page_task_executor_until_eval_equals(
+            &mut vm,
+            &loader,
+            "String(__stopSiblingLoaded)",
+            "true",
+            "a sibling should load while the stopped child remains unchanged",
+        )
+        .await;
+        assert_eq!(
+            vm.eval("__stopSnapshot()")
+                .expect("stopped child snapshot should evaluate"),
+            UNCHANGED,
+            "{action} must not commit from a queued navigation task"
+        );
+
+        vm.eval("__stopFrame.contentWindow.location.assign('/after-stop.html')")
+            .expect("navigation after stop should schedule");
+        advance_page_task_executor_until_eval_equals(
+            &mut vm,
+            &loader,
+            "String(__stopLoads)",
+            "2",
+            "stopping a navigation must not disable later navigations",
+        )
+        .await;
+        assert_eq!(
+            vm.eval("__stopFrame.contentWindow.location.pathname")
+                .expect("resumed child URL should evaluate"),
+            "/after-stop.html"
+        );
+        assert_eq!(
+            server.finish_targets().await,
+            ["/child.html", "/sibling.html", "/after-stop.html"],
+            "{action} must not start the canceled request"
+        );
+    }
+}
+
+#[test]
+fn window_stop_in_child_does_not_cancel_the_top_level_navigation() {
+    let mut vm = new_storage_test_vm("https://window-stop.test/page.html");
+    vm.eval(
+        r#"
+globalThis.__stopFrame = document.createElement('iframe');
+__stopFrame.srcdoc = '<body>child</body>';
+(document.body || document.documentElement || document).appendChild(__stopFrame);
+"#,
+    )
+    .expect("child setup should evaluate");
+    vm.drain_pending_child_frame_work_for_test();
+    vm.eval(
+        r#"
+const child = __stopFrame.contentWindow;
+const childResult = child.navigation.navigate('/child-next.html');
+childResult.committed.catch(() => {});
+childResult.finished.catch(() => {});
+const topResult = navigation.navigate('/top-next.html');
+topResult.committed.catch(() => {});
+topResult.finished.catch(() => {});
+child.stop();
+"#,
+    )
+    .expect("stopping the child should leave the parent navigation alone");
+    assert_eq!(
+        vm.take_pending_location_navigation_with_seed()
+            .expect("the top-level navigation must remain pending")
+            .url
+            .as_str(),
+        "https://window-stop.test/top-next.html"
+    );
+}
+
+#[tokio::test]
+async fn window_stop_discards_in_flight_child_navigation_completions() {
+    let (child_url, request_rx, release_tx, server) =
+        spawn_gated_child_document_resource_server(200).await;
+    let loader = ResourceRequestClient::new(&moli_fetch::FetchConfig::default()).expect("loader");
+    let mut vm = new_storage_page_task_executor_test_vm_with_loader(
+        &child_url.replace("/child.html", "/page.html"),
+        &loader,
+    );
+    vm.eval(
+        r#"
+globalThis.__stopFrame = document.createElement('iframe');
+globalThis.__stopLoads = 0;
+__stopFrame.onload = () => ++__stopLoads;
+__stopFrame.srcdoc = '<body>original</body>';
+(document.body || document.documentElement || document).appendChild(__stopFrame);
+"#,
+    )
+    .expect("in-flight navigation child setup should evaluate");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__stopLoads)",
+        "1",
+        "srcdoc should finish before starting the blocked response",
+    )
+    .await;
+    vm.eval(&format!(
+        "globalThis.__stopDocument = __stopFrame.contentDocument; __stopFrame.contentWindow.location.assign({child_url:?});"
+    ))
+    .expect("child navigation should queue");
+    run_page_realm_prerequisite_then_expected_child_frame_semantic_turn(
+        &mut vm,
+        &loader,
+        ChildFrameSemanticTurnKind::NavigationCommit,
+        "navigation commit task should start the child request",
+    )
+    .await;
+    request_rx.await.expect("the child request should arrive");
+    assert_eq!(
+        vm.eval("__stopFrame.contentWindow.location.href")
+            .expect("in-flight child URL should evaluate"),
+        "about:srcdoc"
+    );
+    vm.eval("__stopFrame.contentWindow.stop()")
+        .expect("in-flight child navigation should stop");
+    release_tx.send(()).expect("release the canceled response");
+    server.await.expect("the gated server should finish");
+    wait_for_one_page_resource_completion_selected_task_executor_test_turn(
+        &mut vm,
+        &loader,
+        "late navigation completion should be discarded",
+    )
+    .await;
+    assert_eq!(
+        vm.eval(
+            "[__stopFrame.contentDocument === __stopDocument, __stopFrame.contentWindow.location.href, __stopLoads].join('|')"
+        )
+        .expect("late response must not replace the stopped child"),
+        "true|about:srcdoc|1"
+    );
+}
+
+#[tokio::test]
+async fn window_stop_preserves_child_cross_document_history_traversal() {
+    let server = StaticHttpServer::spawn(3).await;
+    let parent_url = server.url_for_host("window-stop-traversal.test", "/page.html");
+    let loader = static_http_loader([server.resolve_entry("window-stop-traversal.test")]);
+    let mut vm = new_storage_page_task_executor_test_vm_with_loader(parent_url.as_str(), &loader);
+    vm.eval(
+        r#"
+globalThis.__stopFrame = document.createElement('iframe');
+globalThis.__stopLoads = 0;
+__stopFrame.onload = () => ++__stopLoads;
+__stopFrame.src = '/one.html';
+(document.body || document.documentElement || document).appendChild(__stopFrame);
+"#,
+    )
+    .expect("traversal child setup should evaluate");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__stopLoads)",
+        "1",
+        "first child document should load",
+    )
+    .await;
+    vm.eval("__stopFrame.contentWindow.location.assign('/two.html')")
+        .expect("second child navigation should schedule");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__stopLoads)",
+        "2",
+        "second child document should load",
+    )
+    .await;
+    vm.eval("__stopFrame.contentWindow.history.back()")
+        .expect("child history traversal should schedule");
+    assert!(
+        vm.run_one_history_traversal_executor_turn(&loader)
+            .await
+            .expect("the history task should prepare the cross-document traversal")
+    );
+    vm.eval("__stopFrame.contentWindow.stop()")
+        .expect("stop during traversal should evaluate");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__stopLoads)",
+        "3",
+        "window.stop must not cancel a session history traversal",
+    )
+    .await;
+    assert_eq!(
+        vm.eval("__stopFrame.contentWindow.location.pathname")
+            .expect("traversed URL should evaluate"),
+        "/one.html"
+    );
+    assert_eq!(
+        server.finish_targets().await,
+        ["/one.html", "/two.html", "/one.html"]
+    );
+}
+
 #[tokio::test]
 async fn window_stop_cancels_pending_precommit_before_commit() {
     let loader = ResourceRequestClient::new(&moli_fetch::FetchConfig::default()).expect("loader");
diff --git a/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface.rs b/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface.rs
index a75aa7347e..cfc8606f1e 100644
--- a/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface.rs
+++ b/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface.rs
@@ -12687,13 +12687,21 @@ async fn child_sandbox_blocks_meta_refresh_when_it_is_created() {
 
 #[tokio::test]
 async fn child_meta_refresh_remains_scheduled_when_sandbox_is_added_later() {
-    let loader = ResourceRequestClient::new(&moli_fetch::FetchConfig::default()).expect("loader");
-    let mut vm = new_storage_test_vm_with_loader("https://child-meta-refresh.test/", &loader);
+    let server = StaticHttpServer::spawn(1).await;
+    let parent_url = server.url_for_host("child-meta-refresh.test", "/");
+    let loader = static_http_loader([server.resolve_entry("child-meta-refresh.test")]);
+    let mut vm = new_storage_page_task_executor_test_vm_with_loader(parent_url.as_str(), &loader);
 
     vm.eval(
         r#"
 (() => {
   const frame = document.createElement('iframe');
+  globalThis.__childMetaRefreshLoads = 0;
+  frame.onload = () => {
+    if (++__childMetaRefreshLoads === 1) {
+      frame.setAttribute('sandbox', 'allow-same-origin');
+    }
+  };
   frame.srcdoc = '<meta http-equiv="refresh" content="0;url=#allowed"><p>source</p>';
   (document.body || document.documentElement || document).appendChild(frame);
   return 'ready';
@@ -12701,21 +12709,22 @@ async fn child_meta_refresh_remains_scheduled_when_sandbox_is_added_later() {
 "#,
     )
     .expect("unsandboxed child refresh setup should evaluate");
-    vm.drain_pending_child_frame_work_for_test();
-    vm.eval(
-        "document.querySelector('iframe').setAttribute('sandbox', 'allow-same-origin'); 'added'",
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__childMetaRefreshLoads)",
+        "2",
+        "the scheduled refresh should load after the sandbox is added",
     )
-    .expect("sandbox addition should evaluate");
-    vm.advance_timers_until_deadline_for_test(&loader)
-        .await
-        .expect("scheduled child refresh should run");
+    .await;
 
     assert_eq!(
         vm.eval("document.querySelector('iframe').contentWindow.location.href")
             .expect("child URL should remain observable"),
-        "https://child-meta-refresh.test/#allowed",
+        format!("{parent_url}#allowed"),
         "the sandbox policy is checked when the refresh is created, not again when it becomes due"
     );
+    assert_eq!(server.finish_targets().await, ["/"]);
 }
 
 #[tokio::test]