diff --git a/packages/docusaurus-theme-classic/src/theme/NavbarItem/DocNavbarItem.tsx b/packages/docusaurus-theme-classic/src/theme/NavbarItem/DocNavbarItem.tsx
index f5f60c665a..a0b496bec8 100644
--- a/packages/docusaurus-theme-classic/src/theme/NavbarItem/DocNavbarItem.tsx
+++ b/packages/docusaurus-theme-classic/src/theme/NavbarItem/DocNavbarItem.tsx
@@ -27,11 +27,10 @@ export default function DocNavbarItem({
 
   const doc = version.docs.find((versionDoc) => versionDoc.id === docId);
   if (!doc) {
+    const docIds = version.docs.map((versionDoc) => versionDoc.id).join('\n- ');
     throw new Error(
-      `DocNavbarItem: couldn't find any doc with id=${docId} in version ${
-        version.name
-      }.
-Available docIds=\n- ${version.docs.join('\n- ')}`,
+      `DocNavbarItem: couldn't find any doc with id=${docId} in version ${version.name}.
+Available docIds=\n- ${docIds}`,
     );
   }