From 57ab5b9655a094d1f7e9256fc4505ee4809c5d42 Mon Sep 17 00:00:00 2001
From: "Davide P. Cervone" <dpvc@union.edu>
Date: Fri, 24 Nov 2023 11:02:19 -0500
Subject: [PATCH] Don't descend into items that aren't broken when looking for
 the line break node.  (mathjax/MathJax#3135)

---
 ts/output/common/Wrapper.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ts/output/common/Wrapper.ts b/ts/output/common/Wrapper.ts
index 2ab30d1e8..4d324e4bf 100644
--- a/ts/output/common/Wrapper.ts
+++ b/ts/output/common/Wrapper.ts
@@ -625,7 +625,10 @@ export class CommonWrapper<
    * @return {[WW, WW]}        The embellished mo node and its core mo
    */
   public getBreakNode(bbox: LineBBox): [WW, WW] {
-    const [i, j] = bbox.start || [0, 0];
+    if (!bbox.start) {
+      return [this, null] as any as [WW, WW];
+    }
+    const [i, j] = bbox.start;
     if (this.node.isEmbellished) {
       return [this, this.coreMO()] as any as [WW, WW];
     }