diff --git a/moli-renderer-v8/src/native_bridge/context_host/child_frame_runtime/realm_state/initialize.rs b/moli-renderer-v8/src/native_bridge/context_host/child_frame_runtime/realm_state/initialize.rs
index d271cf6c5d..2ee1e65580 100644
--- a/moli-renderer-v8/src/native_bridge/context_host/child_frame_runtime/realm_state/initialize.rs
+++ b/moli-renderer-v8/src/native_bridge/context_host/child_frame_runtime/realm_state/initialize.rs
@@ -172,13 +172,28 @@ fn bind_frame_element<'s>(
     handle: crate::document_runtime::DomHandle,
 ) {
     let host_ptr = host as *mut JsContextHost;
-    if let Some(frame_element) = host
-        .native_bridge_mut()
-        .wrap_handle(scope, host_ptr, handle)
-        .map(Into::into)
-    {
-        set_private_value(scope, global, "__moliWindowFrameElement", frame_element);
-    }
+    let Some(owner_context) =
+        crate::native_bridge::node::node_owner_document_relevant_context(scope, host_ptr, handle)
+    else {
+        return;
+    };
+    let frame_element = {
+        let owner_scope = &mut v8::ContextScope::new(scope, owner_context);
+        let Some(frame_element) =
+            host.native_bridge_mut()
+                .wrap_handle(owner_scope, host_ptr, handle)
+        else {
+            return;
+        };
+        v8::Global::new(owner_scope, frame_element)
+    };
+    let frame_element = v8::Local::new(scope, &frame_element);
+    set_private_value(
+        scope,
+        global,
+        "__moliWindowFrameElement",
+        frame_element.into(),
+    );
 }
 
 fn bind_navigation<'s>(
diff --git a/moli-renderer-v8/src/native_bridge/element/activation/default_action.rs b/moli-renderer-v8/src/native_bridge/element/activation/default_action.rs
index 7f84666dfc..b647cb6cd6 100644
--- a/moli-renderer-v8/src/native_bridge/element/activation/default_action.rs
+++ b/moli-renderer-v8/src/native_bridge/element/activation/default_action.rs
@@ -1890,14 +1890,22 @@ fn anchor_click_default_action(
             None,
         );
     }
-    let declared_target_name =
-        element_attribute(runtime, handle, "target").filter(|value| !value.is_empty());
+    let effective_target_name = element_attribute(runtime, handle, "target")
+        .filter(|value| !value.is_empty())
+        .or_else(|| {
+            let document = runtime.dom_host().owner_document_handle(handle)?;
+            runtime
+                .dom_host()
+                .document_base_target_for_handle(document)
+                .filter(|target| !target.is_empty())
+                .map(str::to_owned)
+        });
     let (target_name, popup_disposition) = match navigation_policy {
         HyperlinkNavigationPolicy::Auxiliary(disposition) => {
             (Some("_blank".to_owned()), disposition)
         }
         HyperlinkNavigationPolicy::Current => {
-            (declared_target_name, RendererPopupDisposition::Foreground)
+            (effective_target_name, RendererPopupDisposition::Foreground)
         }
         HyperlinkNavigationPolicy::Download => {
             unreachable!("download hyperlink policy returned before target selection")
diff --git a/moli-renderer-v8/src/native_bridge/node.rs b/moli-renderer-v8/src/native_bridge/node.rs
index 396c93df74..3432e300d8 100644
--- a/moli-renderer-v8/src/native_bridge/node.rs
+++ b/moli-renderer-v8/src/native_bridge/node.rs
@@ -1346,6 +1346,9 @@ pub(super) fn node_owner_document_relevant_context<'s>(
     let document_handle = unsafe { &*runtime_ptr }
         .dom_host()
         .owner_document_handle(handle)?;
+    if document_handle == unsafe { &*runtime_ptr }.document_handle() {
+        return unsafe { &*runtime_ptr }.page_default_context(scope);
+    }
     if let Some(child_handle) =
         unsafe { &*runtime_ptr }.child_browsing_context_host_for_document_handle(document_handle)
         && let Some(context) =
diff --git a/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface/extracted/window_and_frame_surfaces.rs b/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface/extracted/window_and_frame_surfaces.rs
index 54993a9add..c2f170fa36 100644
--- a/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface/extracted/window_and_frame_surfaces.rs
+++ b/moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface/extracted/window_and_frame_surfaces.rs
@@ -675,6 +675,111 @@ fn child_webassembly_constructors_use_newtarget_child_realm_default_prototype()
         r#"{"namespaceIsSeparate":true,"constructorFunctionPrototype":true,"moduleDirect":true,"moduleBound":true,"moduleProxy":true,"moduleProxyBound":true,"memoryProxy":true,"compileErrorDirect":true,"moduleTopRealm":true,"moduleIntrinsicSurvivesNamespaceReplacement":true}"#
     );
 }
+#[tokio::test(flavor = "current_thread")]
+async fn base_target_navigation_exposes_replacement_document_before_iframe_load() {
+    const HOST: &str = "anchor-base-target.test";
+
+    let server = StaticHttpServer::spawn(3).await;
+    let top_url = server.url_for_host(HOST, "/path/page.html");
+    let replacement_url = server.url_for_host(HOST, "/replacement.html");
+    let loader = static_http_loader([server.resolve_entry(HOST)]);
+    let mut vm = new_storage_page_task_executor_test_vm_with_loader(top_url.as_str(), &loader);
+
+    vm.eval(
+        r#"
+(() => {
+  globalThis.__targetLoadCount = 0;
+  globalThis.__targetLoadAccess = "pending";
+  globalThis.__frameLoadCount = 0;
+  globalThis.__baseTargetOwnerRealm = "pending";
+
+  const root = document.documentElement || document.appendChild(document.createElement('html'));
+  const body = document.body || root.appendChild(document.createElement('body'));
+  document.addEventListener('load', () => { __frameLoadCount += 1; }, true);
+  body.innerHTML = `
+    <iframe id="base-target-source" name="sourceFrame" src="/source.html"></iframe>
+    <iframe id="base-target-target" name="targetFrame" src="/target.html"></iframe>
+  `;
+})()
+"#,
+    )
+    .expect("base-target network child setup should evaluate");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__frameLoadCount)",
+        "2",
+        "initial parser-created base-target child documents should load",
+    )
+    .await;
+
+    vm.eval(
+        r#"
+(() => {
+  const source = document.getElementById('base-target-source');
+  const target = document.getElementById('base-target-target');
+  __baseTargetOwnerRealm = [
+    source instanceof HTMLIFrameElement,
+    target instanceof HTMLIFrameElement,
+    target instanceof target.contentWindow.HTMLIFrameElement,
+    target.contentWindow.frameElement === target
+  ].join('|');
+
+  const doc = source.contentDocument;
+  const firstBase = doc.createElement('base');
+  firstBase.target = 'targetFrame';
+  const secondBase = doc.createElement('base');
+  secondBase.target = '_self';
+  doc.head.append(firstBase, secondBase);
+
+  const link = doc.createElement('a');
+  link.href = '/replacement.html';
+  link.setAttribute('target', '');
+  doc.body.appendChild(link);
+
+  target.addEventListener('load', () => {
+    __targetLoadCount += 1;
+    try {
+      __targetLoadAccess = target.contentDocument.location.href;
+    } catch (error) {
+      __targetLoadAccess = `${error && error.name}:${error && error.message}`;
+    }
+  }, true);
+  link.click();
+})()
+"#,
+    )
+    .expect("base-target replacement navigation should start");
+    advance_page_task_executor_until_eval_equals(
+        &mut vm,
+        &loader,
+        "String(__targetLoadCount)",
+        "1",
+        "base-target replacement document should load",
+    )
+    .await;
+
+    assert_eq!(
+        vm.eval("__baseTargetOwnerRealm")
+            .expect("base-target frame owner realm result should evaluate"),
+        "true|true|false|true",
+        "parser-created frame elements and window.frameElement must use the owner Document realm"
+    );
+    assert_eq!(
+        vm.eval("__targetLoadAccess")
+            .expect("target load callback access result should evaluate"),
+        replacement_url.as_str(),
+        "the replacement Document must be same-origin accessible during the iframe load callback"
+    );
+
+    let mut targets = server.finish_targets().await;
+    targets.sort();
+    assert_eq!(
+        targets,
+        ["/replacement.html", "/source.html", "/target.html"]
+    );
+}
+
 #[test]
 fn targeted_anchor_click_reports_same_document_hash_change_for_child_window() {
     let mut vm = new_storage_test_vm("https://targeted-child-hash.test/page.html");