From 0d6fe56b8085d812b4efe310a27708d01d8f130f Mon Sep 17 00:00:00 2001
From: Yanzhen Yu <yanzhen@smartx.com>
Date: Wed, 1 Apr 2026 12:00:00 +0800
Subject: [PATCH] close #263 Since we improved the block class strategy, we
 need to check parent node before pushAdd.

---
 src/record/mutation.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/record/mutation.ts b/src/record/mutation.ts
index c1e29134..0577858b 100644
--- a/src/record/mutation.ts
+++ b/src/record/mutation.ts
@@ -78,6 +78,9 @@ export default class MutationBuffer {
      */
     const addQueue: Node[] = [];
     const pushAdd = (n: Node) => {
+      if (!n.parentNode) {
+        return;
+      }
       const parentId = mirror.getId((n.parentNode as Node) as INode);
       const nextId =
         n.nextSibling && mirror.getId((n.nextSibling as unknown) as INode);