diff --git a/packages/mermaid/src/rendering-util/render.ts b/packages/mermaid/src/rendering-util/render.ts
index 56bccab94..3062cf5ca 100644
--- a/packages/mermaid/src/rendering-util/render.ts
+++ b/packages/mermaid/src/rendering-util/render.ts
@@ -41,7 +41,7 @@ const registerDefaultLayoutLoaders = () => {
     },
     {
       name: 'ipsepCola',
-      loader: async () => await import('./layout-algorithms/ipsepCola/index.ts'),
+      loader: async () => await import('./layout-algorithms/ipsepCola/index.js'),
     },
   ]);
 };