diff --git a/ui/src/app/app-host.test.ts b/ui/src/app/app-host.test.ts
index f50a80504366..7456b08238d8 100644
--- a/ui/src/app/app-host.test.ts
+++ b/ui/src/app/app-host.test.ts
@@ -19,6 +19,7 @@ import { SESSION_FACE_PREFERENCE_PARAM } from "../lib/sessions/route-navigation.
 import { createStorageMock } from "../test-helpers/storage.ts";
 import { selectShellRouteState } from "./app-host-route-state.ts";
 import { resetAppHostTestGlobals, type ShellKeyboardState } from "./app-host.test-support.ts";
+import { ShellGatewayOwner, type ShellGatewayHost } from "./app-shell-gateway.ts";
 import "./app-host.ts";
 import type {
   ApplicationContext,
@@ -60,11 +61,6 @@ type ShellInitializationState = {
   ) => void;
 };
 
-type ShellGatewaySynchronizationState = {
-  outboxStoreImport: { load: () => Promise<unknown> };
-  synchronizeGateway: (snapshot: ApplicationGatewaySnapshot) => void;
-};
-
 type I18nRecoveryWiring = {
   localeLoadRecovery?: {
     isUnrecoverableError: (error: unknown) => boolean;
@@ -319,10 +315,27 @@ describe("OpenClaw shell source initialization", () => {
 
   it("retries a pending locale once when the Gateway becomes connected", () => {
     const retryPendingLocale = vi.spyOn(i18n, "retryPendingLocale").mockImplementation(() => {});
-    const shell = document.createElement(
-      "openclaw-app-shell",
-    ) as unknown as ShellGatewaySynchronizationState;
-    shell.outboxStoreImport = { load: vi.fn(async () => undefined) };
+    // Owner-direct: the shared jsdom lane can retain a sibling graph's
+    // openclaw-app-shell class bound to a different i18n instance; constructing
+    // the owner keeps the spy and the callee in the current module graph.
+    const host = {
+      activeSessionKey: "",
+      agentRosterRefreshTimer: null,
+      agentsListClient: null,
+      agentsListSource: null,
+      context: undefined,
+      criticalNoticeRuntime: null,
+      lastLocalePrefSignature: null,
+      outboxStoreImport: { load: vi.fn(async () => undefined) },
+      previousGatewayPhase: null,
+      routeState: {},
+      runtimeConfigClient: null,
+      runtimeConfigSource: null,
+      sessionKeyClient: null,
+      sidebarWorkboardRuntime: null,
+      syncSidebarWorkboard: vi.fn(),
+    } as unknown as ShellGatewayHost;
+    const owner = new ShellGatewayOwner(host);
     const reconnecting = {
       client: null,
       phase: "reconnecting",
@@ -334,10 +347,10 @@ describe("OpenClaw shell source initialization", () => {
       sessionKey: "",
     } as ApplicationGatewaySnapshot;
 
-    shell.synchronizeGateway(reconnecting);
-    shell.synchronizeGateway(connected);
-    shell.synchronizeGateway({ ...connected });
-    shell.synchronizeGateway({ ...connected });
+    owner.synchronizeGateway(reconnecting);
+    owner.synchronizeGateway(connected);
+    owner.synchronizeGateway({ ...connected });
+    owner.synchronizeGateway({ ...connected });
 
     expect(retryPendingLocale).toHaveBeenCalledOnce();
     retryPendingLocale.mockRestore();
diff --git a/ui/src/app/native-link-routing.test.ts b/ui/src/app/native-link-routing.test.ts
index d2217b7d7cfc..09da7e33599a 100644
--- a/ui/src/app/native-link-routing.test.ts
+++ b/ui/src/app/native-link-routing.test.ts
@@ -100,6 +100,45 @@ describe("native link routing", () => {
     ]);
   });
 
+  it("defines the hovercard once across duplicate bootstrap module instances", async () => {
+    // Regression: the non-isolated jsdom lane evaluates the registration
+    // module once per sibling file against one persistent document, so stale
+    // bootstrap listeners fire alongside this file's own. Reproduce that order
+    // and require a single registry definition.
+    vi.resetModules();
+    await import("../components/github-link-hovercard-registration.ts");
+    const define = vi.spyOn(customElements, "define");
+    const provider = document.createElement(
+      "openclaw-github-link-hovercard-provider",
+    ) as GitHubLinkHovercardProvider;
+    provider.client = {
+      request: vi.fn().mockResolvedValue({
+        comments: 1,
+        createdAt: "2026-07-09T10:00:00Z",
+        kind: "issue",
+        login: "octocat",
+        number: 102691,
+        owner: "openclaw",
+        repo: "openclaw",
+        state: "open",
+        title: "Open links in a sidebar browser",
+        updatedAt: "2026-07-09T10:00:00Z",
+      }),
+    } as unknown as GatewayBrowserClient;
+    const anchor = document.createElement("a");
+    anchor.href = "https://github.com/openclaw/openclaw/issues/102691";
+    anchor.textContent = "#102691";
+    provider.append(anchor);
+    document.body.append(provider);
+    anchor.focus();
+    await vi.waitFor(() => expect(document.querySelector(".github-link-hovercard")).not.toBeNull());
+    const hovercardDefines = define.mock.calls.filter(
+      ([tag]) => tag === "openclaw-github-link-hovercard-provider",
+    );
+    expect(hovercardDefines).toHaveLength(1);
+    define.mockRestore();
+  });
+
   it("closes an active GitHub hovercard after routing its link", async () => {
     const bridge = installBridge();
     routing = startNativeLinkRouting();
diff --git a/ui/src/app/route-transition.test.ts b/ui/src/app/route-transition.test.ts
index 0ad53c8c10f1..960d2c1799c9 100644
--- a/ui/src/app/route-transition.test.ts
+++ b/ui/src/app/route-transition.test.ts
@@ -5,9 +5,11 @@ function testDocumentWithOutlet(animate = vi.fn()) {
   const outlet = document.createElement("openclaw-router-outlet") as HTMLElement & {
     updateComplete: Promise<void>;
   };
+  // Own data property: the real OpenClawRouterOutlet may already be registered by a
+  // sibling test in this worker, and Lit's updateComplete is a getter-only accessor.
   Object.defineProperty(outlet, "updateComplete", {
-    configurable: true,
     value: Promise.resolve(),
+    configurable: true,
   });
   outlet.animate = animate;
   document.body.append(outlet);
diff --git a/ui/src/components/github-link-hovercard-registration.ts b/ui/src/components/github-link-hovercard-registration.ts
index fc0f3385b5a5..0dc5bffe4fc6 100644
--- a/ui/src/components/github-link-hovercard-registration.ts
+++ b/ui/src/components/github-link-hovercard-registration.ts
@@ -40,7 +40,12 @@ async function activateHovercard(event: Event, trigger: "focus" | "pointer"): Pr
   );
   await ensureCustomElementDefined(HOVERCARD_TAG, async () => {
     const runtime = await import("./github-link-hovercard.runtime.ts");
-    customElements.define(HOVERCARD_TAG, runtime.GitHubLinkHovercardProvider);
+    // Sibling module instances can share one document + registry (the
+    // non-isolated jsdom lane evaluates this module once per test file), so a
+    // concurrent instance may have defined the tag while our load resolved.
+    if (!customElements.get(HOVERCARD_TAG)) {
+      customElements.define(HOVERCARD_TAG, runtime.GitHubLinkHovercardProvider);
+    }
     for (const [provider, client] of pendingClients) {
       provider.client = client;
     }