--- gthumb/gth-toolbox.c.orig	2015-05-27 15:17:29.000000000 -0700
+++ gthumb/gth-toolbox.c	2015-05-27 15:18:43.000000000 -0700
@@ -318,7 +318,7 @@
 		column[i] = -1;
 	}
 
-	for (i = 0; i < children->len; i++) {
+	for (i = 0; i < children->len - 1; i++) {
 		GType      child_type;
 		GtkWidget *child;
 		int        section;