diff --git a/src/app/data_types_internal.ts b/src/app/data_types_internal.ts
index 18db32d..a4dc363 100644
--- a/src/app/data_types_internal.ts
+++ b/src/app/data_types_internal.ts
@@ -555,6 +555,7 @@ export interface IconConfig {
   iconset?: string;
   color?: string;
   size?: 'small'|'medium'|'large';
+  cmIcon?: SVGSVGElement;  // optional cm-icon
 }
 
 /**