From f3daf986b13332fb90bbe7369a973fb7a0d33cfc Mon Sep 17 00:00:00 2001
From: Dmitry Vasilev <dmitry.vasil@gmail.com>
Date: Thu, 13 Jul 2023 16:40:55 +0300
Subject: [PATCH] fix

---
 src/editor/value_explorer.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/editor/value_explorer.js b/src/editor/value_explorer.js
index 9b038ce..ef64304 100644
--- a/src/editor/value_explorer.js
+++ b/src/editor/value_explorer.js
@@ -12,7 +12,7 @@ import {with_code_execution} from '../index.js'
 // come both from app_window and current window (where they are created in
 // metacircular interpreter
 const has_custom_toString = object =>
-  object.toString != null
+  typeof(object.toString) == 'function'
   && object.toString != globalThis.app_window.Object.prototype.toString
   && object.toString != Object.prototype.toString