From b0d2094bb3123e2abe4d24c3baf9e3fa2f7c2d80 Mon Sep 17 00:00:00 2001
From: Rens Tillmann <feeling4design@gmail.com>
Date: Fri, 17 Jan 2020 16:37:30 +0100
Subject: [PATCH] Update backbone.js

Fix: JS TypeError. In case the _listeners object is undefined it will trigger an error.
---
 backbone.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/backbone.js b/backbone.js
index 4ed524e89..74d5d5c98 100644
--- a/backbone.js
+++ b/backbone.js
@@ -374,7 +374,7 @@
   // Cleans up memory bindings between the listener and the listenee.
   Listening.prototype.cleanup = function() {
     delete this.listener._listeningTo[this.obj._listenId];
-    if (!this.interop) delete this.obj._listeners[this.id];
+    if (!this.interop && typeof this.obj._listeners !== 'undefined' ) delete this.obj._listeners[this.id];
   };
 
   // Aliases for backwards compatibility.