webui: supress mermaid error msgs
diff --git a/webui/src/web-components/sketch-timeline-message.ts b/webui/src/web-components/sketch-timeline-message.ts
index 1e950d5..118fe36 100644
--- a/webui/src/web-components/sketch-timeline-message.ts
+++ b/webui/src/web-components/sketch-timeline-message.ts
@@ -441,6 +441,7 @@
     // Initialize mermaid with specific config
     mermaid.initialize({
       startOnLoad: false,
+      suppressErrorRendering: true,
       theme: "default",
       securityLevel: "loose", // Allows more flexibility but be careful with user-generated content
       fontFamily: "monospace",