diff --git a/moli-renderer-v8/src/worker/thread/mod.rs b/moli-renderer-v8/src/worker/thread/mod.rs
index f42bcd7bf9..f4896d14e7 100644
--- a/moli-renderer-v8/src/worker/thread/mod.rs
+++ b/moli-renderer-v8/src/worker/thread/mod.rs
@@ -2677,7 +2677,16 @@ async fn worker_main(
                         callback_context: None,
                         exception: None,
                     };
-                    if !dispatch_worker_error_event(scope, global, &report, None, &script_url) {
+                    // Propagation to the owner's global uses omitError: the
+                    // child exception cannot cross the worker agent boundary.
+                    let omitted_error = v8::null(scope).into();
+                    if !dispatch_worker_error_event(
+                        scope,
+                        global,
+                        &report,
+                        Some(omitted_error),
+                        &script_url,
+                    ) {
                         report_exception_to_parent(
                             &report,
                             &script_url,
diff --git a/moli-renderer-v8/src/worker/thread/tests/lifecycle/worker_errors_and_teardown.rs b/moli-renderer-v8/src/worker/thread/tests/lifecycle/worker_errors_and_teardown.rs
index 6987265257..1a4d626be5 100644
--- a/moli-renderer-v8/src/worker/thread/tests/lifecycle/worker_errors_and_teardown.rs
+++ b/moli-renderer-v8/src/worker/thread/tests/lifecycle/worker_errors_and_teardown.rs
@@ -899,7 +899,7 @@ async fn nested_worker_unhandled_error_routes_through_parent_worker_onerror() {
             postMessage({
                 messageIncludesBoom: String(message).includes("child-boom"),
                 filenameIncludesDataUrl: String(filename).includes("data:text/javascript"),
-                errorIsUndefined: error === undefined
+                errorIsNull: error === null
             });
             close();
             return true;
@@ -916,7 +916,7 @@ async fn nested_worker_unhandled_error_routes_through_parent_worker_onerror() {
         .expect("channel closed");
     assert_eq!(
         expect_post_json(msg),
-        r#"{"messageIncludesBoom":true,"filenameIncludesDataUrl":true,"errorIsUndefined":true}"#
+        r#"{"messageIncludesBoom":true,"filenameIncludesDataUrl":true,"errorIsNull":true}"#
     );
 }