diff -up zenity-3.8.0/src/zenity.ui.list-expand zenity-3.8.0/src/zenity.ui
--- zenity-3.8.0/src/zenity.ui.list-expand	2015-08-19 14:04:38.907058018 -0400
+++ zenity-3.8.0/src/zenity.ui	2015-08-19 14:04:54.619268454 -0400
@@ -1026,6 +1026,7 @@
                     <property name="visible">True</property>
                     <property name="can_focus">True</property>
                     <property name="has_focus">True</property>
+                    <property name="vexpand">True</property>
                     <child internal-child="selection">
                       <object class="GtkTreeSelection" id="treeview-selection1"/>
                     </child>