From 7fbf03f699199da6f91aa078fd9c44ed40023c71 Mon Sep 17 00:00:00 2001
From: Jovi De Croock <decroockjovi@gmail.com>
Date: Fri, 5 Apr 2024 11:28:41 +0200
Subject: [PATCH] fix: check whether `oldDom` is present in the DOM (#4318)

* leverage isConnected

* expect ts error
---
 src/diff/children.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/diff/children.js b/src/diff/children.js
index eba002d56d..1b4d6b55dc 100644
--- a/src/diff/children.js
+++ b/src/diff/children.js
@@ -116,7 +116,8 @@ export function diffChildren(
 			childVNode._flags & INSERT_VNODE ||
 			oldVNode._children === childVNode._children
 		) {
-			if (!newDom && oldVNode._dom == oldDom) {
+			// @ts-expect-error olDom should be present on a DOM node
+			if (oldDom && !oldDom.isConnected) {
 				oldDom = getDomSibling(oldVNode);
 			}
 			oldDom = insert(childVNode, oldDom, parentDom);