From fe63b4a187bd0865950ed1b61e076cfd1c75a365 Mon Sep 17 00:00:00 2001
From: Mellisa Hankins <mell@milkywaymultimedia.com.au>
Date: Wed, 4 Mar 2015 10:40:53 +1100
Subject: [PATCH] FIX: Don't try to remove sortable if it doesn't exist in the
 first place

---
 javascript/GridFieldExtensions.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/javascript/GridFieldExtensions.js b/javascript/GridFieldExtensions.js
index fbfe90c..3011cce 100644
--- a/javascript/GridFieldExtensions.js
+++ b/javascript/GridFieldExtensions.js
@@ -205,7 +205,8 @@
 				});
 			},
 			onremove: function() {
-				this.sortable("destroy");
+                if(this.data('sortable'))
+				    this.sortable("destroy");
 			}
 		});