diff --git a/index.d.ts b/index.d.ts
index 6894b9b13..8d7f37c0c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -279,6 +279,10 @@ declare namespace grapesjs {
     dropzoneContent?: string;
     modalTitle?: string;
     inputPlaceholder?: string;
+    custom?: boolean | {
+      open?: (props: any) => void,
+      close?: (props: any) => void,
+    };
   }
 
   interface CanvasConfig {