Hash fragment redirects trigger “Something went wrong” error on Uniswap web landing page

[5m477]

Interface Affected

• [x] Web (app.uniswap.org)

---

App Version

• Version: Production build (hash-router landing logic)
• [x] Production build

---

System / Environment Info

• Browser: All browsers

---

Steps to Reproduce

1. Open https://app.uniswap.org/#//example.org in a clean browser session.
2. Allow the landing page to finish loading.
3. A "Something went wrong" modal appears with a SecurityError stack trace.

---

Expected Behavior

Ignore external-looking hash fragments or redirect only to internal routes without raising errors.

---

Actual Behavior

• Fragment is passed to React Router's <Navigate>.
• Router calls history.replaceState('https://example.org/'); the browser rejects it with SecurityError.
• User stays on app.uniswap.org but sees the error overlay until reload.

---

Screenshots or Screen Recording

Screenshot available showing the "Something went wrong" overlay with the SecurityError stack trace.

---

Additional Context

• Logic lives in apps/web/src/pages/RouteDefinitions.tsx via <Navigate to={args.hash.replace('#', '')} />.
• Sanitising fragments (e.g., require a leading /) preserves legacy hashes like #/swap while avoiding the error.
• No cross-origin redirect occurs; the issue is limited to a user-visible error state.

---