diff --git a/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.test.tsx b/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.test.tsx
index 8c712e3c1d..e40b1b4f13 100644
--- a/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.test.tsx
+++ b/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.test.tsx
@@ -1,5 +1,5 @@
-import { act, render } from '@testing-library/react';
-import { MemoryRouter, useLocation, useNavigate, type NavigateFunction } from 'react-router-dom';
+import { act, render, renderHook } from '@testing-library/react';
+import { MemoryRouter, useLocation, useNavigate, type Location, type NavigateFunction } from 'react-router-dom';
 import { describe, expect, it } from 'vitest';
 import { useResourceNavigationKey } from './useResourceNavigationKey.js';
 
@@ -58,4 +58,36 @@ describe('useResourceNavigationKey', () => {
 
         expect(last()).not.toBe(first);
     });
+    
+    describe('for a location without history state', () => {
+        const at = (pathname: string, search = ''): Location => ({
+            key: 'default',
+            pathname,
+            search,
+            hash: '',
+            state: null,
+        });
+        const renderAt = (location: Location) =>
+            renderHook(({ location }) => useResourceNavigationKey(location, false), {
+                initialProps: { location },
+            });
+
+        it('changes the key when the path changes', () => {
+            const { result, rerender } = renderAt(at('/finos.calm/interfaces/2/detail'));
+            const first = result.current;
+
+            rerender({ location: at('/namespace/finos.traderx') });
+
+            expect(result.current).not.toBe(first);
+        });
+
+        it('keeps the key when only the query changes', () => {
+            const { result, rerender } = renderAt(at('/finos/patterns/api-gateway/1.0.0'));
+            const first = result.current;
+
+            rerender({ location: at('/finos/patterns/api-gateway/1.0.0', '?tab=json') });
+
+            expect(result.current).toBe(first);
+        });
+    });
 });
diff --git a/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.ts b/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.ts
index 649b312320..b5f782d9de 100644
--- a/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.ts
+++ b/calm-hub-ui/src/hub/hooks/useResourceNavigationKey.ts
@@ -1,6 +1,13 @@
 import { useState } from 'react';
 import type { Location } from 'react-router-dom';
 
+// A location that the router did not create, such as a first page load or a hash that was
+// edited by hand, has no history state, so React Router gives it the key `default`. For those
+// locations the pathname identifies the navigation.
+function navigationId(location: Location): string {
+    return location.key === 'default' ? `${location.key}:${location.pathname}` : location.key;
+}
+
 /**
  * Returns a key that changes on each navigation, except a change to the query only, such as a
  * diagram tab. While the key stays the same, the page keeps the resource it loaded. A navigation
@@ -8,21 +15,22 @@ import type { Location } from 'react-router-dom';
  * so that the route loads the resource again.
  */
 export function useResourceNavigationKey(location: Location, loadFailed: boolean): string {
+    const id = navigationId(location);
     const [last, setLast] = useState({
-        key: location.key,
+        id,
         pathname: location.pathname,
         search: location.search,
-        resourceKey: location.key,
+        resourceKey: id,
     });
-    if (last.key === location.key) return last.resourceKey;
+    if (last.id === id) return last.resourceKey;
 
     const keepsResource = !loadFailed && location.pathname === last.pathname && location.search !== last.search;
     const next = {
-        key: location.key,
+        id,
         pathname: location.pathname,
         search: location.search,
-        resourceKey: keepsResource ? last.resourceKey : location.key,
+        resourceKey: keepsResource ? last.resourceKey : id,
     };
     setLast(next);
     return next.resourceKey;
-}
+}
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