Merge pull request #11542 from backstage/mob/fix-entity-docs-bug

[TechDocs] Fix Entity Docs Routes

.changeset/techdocs-dancers-battle.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-techdocs': patch
+---
+
+Add a `sub-route` path on the EntityDocs page to fix the blank screen error when navigating using sidebar links.

plugins/techdocs/src/Router.tsx

@@ -69,7 +69,9 @@ export const EmbeddedDocsRouter = (props: PropsWithChildren<{}>) => {
 
   return (
     <Routes>
-      <Route element={<EntityPageDocs entity={entity} />}>{children}</Route>
+      <Route path="*" element={<EntityPageDocs entity={entity} />}>
+        {children}
+      </Route>
     </Routes>
   );
 };