diff --git a/docs/index.html b/docs/index.html
index a793da74a23b4..c8a41b4b2b1e7 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -498,7 +498,7 @@ <h1><a href="https://threejs.org">three.js</a></h1>
 			const oldIframe = iframe;
 			iframe = oldIframe.cloneNode();
 
-			if ( hash ) {
+			if ( hash && titles[ splitHash[ 0 ] ] ) {
 
 				iframe.src = splitHash[ 0 ] + '.html' + splitHash[ 1 ];
 				subtitle = titles[ splitHash[ 0 ] ] + splitHash[ 1 ] + ' – ';