diff --git a/src/Markdig/Extensions/Diagrams/DiagramExtension.cs b/src/Markdig/Extensions/Diagrams/DiagramExtension.cs
index b04e889a1..131c951a9 100644
--- a/src/Markdig/Extensions/Diagrams/DiagramExtension.cs
+++ b/src/Markdig/Extensions/Diagrams/DiagramExtension.cs
@@ -22,9 +22,7 @@ public void Setup(MarkdownPipeline pipeline, IMarkdownRenderer renderer)
         if (renderer is HtmlRenderer htmlRenderer)
         {
             var codeRenderer = htmlRenderer.ObjectRenderers.FindExact<CodeBlockRenderer>()!;
-            // TODO: Add other well known diagram languages
-            codeRenderer.BlocksAsDiv.Add("mermaid");
             codeRenderer.BlocksAsDiv.Add("nomnoml");
         }
     }
-}
\ No newline at end of file
+}