Use history.pushState for hash link navigation in techdocs

.changeset/small-berries-travel.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-techdocs': patch
+---
+
+Use `history.pushState` for hash link navigation.

plugins/techdocs/src/reader/components/Reader.tsx

@@ -115,7 +115,15 @@ export const Reader = ({ entityId, onReady }: Props) => {
         baseUrl: window.location.origin,
         onClick: (_: MouseEvent, url: string) => {
           const parsedUrl = new URL(url);
-          navigate(`${parsedUrl.pathname}${parsedUrl.hash}`);
+          if (parsedUrl.hash) {
+            history.pushState(
+              null,
+              '',
+              `${parsedUrl.pathname}${parsedUrl.hash}`,
+            );
+          } else {
+            navigate(parsedUrl.pathname);
+          }
 
           shadowRoot?.querySelector(parsedUrl.hash)?.scrollIntoView();
         },