diff --git a/ui/src/hooks/useKeyboardShortcuts.test.tsx b/ui/src/hooks/useKeyboardShortcuts.test.tsx
new file mode 100644
index 00000000..9d1c59dc
--- /dev/null
+++ b/ui/src/hooks/useKeyboardShortcuts.test.tsx
@@ -0,0 +1,58 @@
+// @vitest-environment jsdom
+
+import { act } from "react";
+import { createRoot } from "react-dom/client";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { useKeyboardShortcuts } from "./useKeyboardShortcuts";
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+(globalThis as any).IS_REACT_ACT_ENVIRONMENT = true;
+
+function TestHarness({
+  onNewIssue,
+}: {
+  onNewIssue: () => void;
+}) {
+  useKeyboardShortcuts({
+    enabled: true,
+    onNewIssue,
+  });
+
+  return <div>keyboard shortcuts test</div>;
+}
+
+describe("useKeyboardShortcuts", () => {
+  let container: HTMLDivElement;
+
+  beforeEach(() => {
+    container = document.createElement("div");
+    document.body.appendChild(container);
+  });
+
+  afterEach(() => {
+    container.remove();
+  });
+
+  it("ignores events already claimed by another handler", () => {
+    const root = createRoot(container);
+    const onNewIssue = vi.fn();
+
+    act(() => {
+      root.render(<TestHarness onNewIssue={onNewIssue} />);
+    });
+
+    const event = new KeyboardEvent("keydown", {
+      key: "c",
+      bubbles: true,
+      cancelable: true,
+    });
+    event.preventDefault();
+    document.dispatchEvent(event);
+
+    expect(onNewIssue).not.toHaveBeenCalled();
+
+    act(() => {
+      root.unmount();
+    });
+  });
+});
diff --git a/ui/src/hooks/useKeyboardShortcuts.ts b/ui/src/hooks/useKeyboardShortcuts.ts
index c917ebba..1502adde 100644
--- a/ui/src/hooks/useKeyboardShortcuts.ts
+++ b/ui/src/hooks/useKeyboardShortcuts.ts
@@ -20,6 +20,10 @@ export function useKeyboardShortcuts({
     if (!enabled) return;
 
     function handleKeyDown(e: KeyboardEvent) {
+      if (e.defaultPrevented) {
+        return;
+      }
+
       // Don't fire shortcuts when typing in inputs
       if (isKeyboardShortcutTextInputTarget(e.target)) {
         return;
diff --git a/ui/src/pages/IssueDetail.tsx b/ui/src/pages/IssueDetail.tsx
index f9939b9b..41d0b25f 100644
--- a/ui/src/pages/IssueDetail.tsx
+++ b/ui/src/pages/IssueDetail.tsx
@@ -1332,11 +1332,13 @@ export function IssueDetail() {
       disarm();
       if (action === "navigate_inbox") {
         event.preventDefault();
+        event.stopPropagation();
         navigate(sourceBreadcrumb.href.startsWith("/inbox") ? sourceBreadcrumb.href : "/inbox");
         return;
       }
       if (action === "focus_comment") {
         event.preventDefault();
+        event.stopPropagation();
         setDetailTab("chat");
         setPendingCommentComposerFocusKey((current) => current + 1);
       }