diff --git a/content/browser/service_worker/service_worker_client_utils.cc b/content/browser/service_worker/service_worker_client_utils.cc
index 84d13a1e7265e..adb3af782cee5 100644
--- a/content/browser/service_worker/service_worker_client_utils.cc
+++ b/content/browser/service_worker/service_worker_client_utils.cc
@@ -285,8 +285,21 @@ void NavigateClientOnUI(const GURL& url,
     return;
   }
 
-  int frame_tree_node_id = rfhi->frame_tree_node()->frame_tree_node_id();
+  // Reject the navigate() call if there is an ongoing browser-initiated
+  // navigation. Not rejecting it would allow websites to prevent the user from
+  // navigating away. See https://crbug.com/930154.
+  NavigationRequest* ongoing_navigation_request =
+      rfhi->frame_tree_node()->frame_tree()->root()->navigation_request();
+  if (ongoing_navigation_request &&
+      ongoing_navigation_request->browser_initiated()) {
+    base::PostTaskWithTraits(
+        FROM_HERE, {BrowserThread::IO},
+        base::BindOnce(std::move(callback), ChildProcessHost::kInvalidUniqueID,
+                       MSG_ROUTING_NONE));
+    return;
+  }
 
+  int frame_tree_node_id = rfhi->frame_tree_node()->frame_tree_node_id();
   Navigator* navigator = rfhi->frame_tree_node()->navigator();
   navigator->RequestOpenURL(
       rfhi, url, url::Origin::Create(script_url), false /* uses_post */,
diff --git a/content/browser/service_worker/service_worker_clients_api_browsertest.cc b/content/browser/service_worker/service_worker_clients_api_browsertest.cc
index 02029fe4100c8..e24d7bd1558d2 100644
--- a/content/browser/service_worker/service_worker_clients_api_browsertest.cc
+++ b/content/browser/service_worker/service_worker_clients_api_browsertest.cc
@@ -258,6 +258,36 @@ IN_PROC_BROWSER_TEST_F(ServiceWorkerClientsApiBrowserTest,
   EXPECT_EQ(title, title_watcher.WaitAndGetTitle());
 }
 
+// Tests a WindowClient.navigate() call during a browser-initiated navigation.
+// Regression test for https://crbug.com/930154.
+IN_PROC_BROWSER_TEST_F(ServiceWorkerClientsApiBrowserTest,
+                       NavigateDuringBrowserNavigation) {
+  // Load a page that registers a service worker.
+  EXPECT_TRUE(NavigateToURL(shell(),
+                            embedded_test_server()->GetURL(
+                                "/service_worker/create_service_worker.html")));
+  EXPECT_EQ("DONE", EvalJs(shell(), "register('client_api_worker.js');"));
+
+  // Load the test page.
+  EXPECT_TRUE(NavigateToURL(
+      shell(),
+      embedded_test_server()->GetURL("/service_worker/request_navigate.html")));
+
+  // Start a browser-initiated navigation.
+  GURL url(embedded_test_server()->GetURL("/title1.html"));
+  TestNavigationManager navigation(shell()->web_contents(), url);
+  shell()->LoadURL(url);
+  EXPECT_TRUE(navigation.WaitForRequestStart());
+
+  // Have the service worker call client.navigate() to try to go to another
+  // URL. It should fail.
+  EXPECT_EQ("navigate failed", EvalJs(shell(), "requestToNavigate();"));
+
+  // The browser-initiated navigation should finish.
+  navigation.WaitForNavigationFinished();  // Resume navigation.
+  EXPECT_TRUE(navigation.was_successful());
+}
+
 // Tests a successful Clients.openWindow() call.
 IN_PROC_BROWSER_TEST_F(ServiceWorkerClientsApiBrowserTest, OpenWindow) {
   ActivatedServiceWorkerObserver observer;
diff --git a/content/test/data/service_worker/client_api_worker.js b/content/test/data/service_worker/client_api_worker.js
index 9127c181fc078..12cfeb2d6e187 100644
--- a/content/test/data/service_worker/client_api_worker.js
+++ b/content/test/data/service_worker/client_api_worker.js
@@ -2,10 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-self.addEventListener('message', event => {
+self.addEventListener('message', async (event) => {
   if (event.data.command == 'navigate') {
     const url = event.data.url;
-    event.source.navigate(url);
+    try {
+      await event.source.navigate(url);
+    } catch (err) {
+      event.source.postMessage('navigate failed');
+    }
   }
 });
 
diff --git a/content/test/data/service_worker/request_navigate.html b/content/test/data/service_worker/request_navigate.html
new file mode 100644
index 0000000000000..c7a097abe8e59
--- /dev/null
+++ b/content/test/data/service_worker/request_navigate.html
@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Request navigate</title>
+<script>
+// Asks the service worker to call WindowClient.navigate() on us. It will
+// message back the result if it failed, or else we navigate away.
+async function requestToNavigate() {
+  const sawMessage = new Promise((resolve) => {
+    navigator.serviceWorker.onmessage = (event) => {
+      resolve(event.data);
+    };
+  });
+  const registration = await navigator.serviceWorker.ready;
+  registration.active.postMessage({command: 'navigate', url: 'empty.html'});
+  return await sawMessage;
+}
+</script>