restore combobox in disco window. Fixes #5656

data/gui/service_discovery_window.ui

@@ -70,13 +70,8 @@ Agent JID - node</property>
               <object class="GtkComboBoxEntry" id="address_comboboxentry">
                 <property name="visible">True</property>
                 <property name="model">liststore1</property>
+                <property name="text_column">0</property>
                 <signal name="changed" handler="on_address_comboboxentry_changed"/>
-                <child>
-                  <object class="GtkCellRendererText" id="cellrenderertext1"/>
-                  <attributes>
-                    <attribute name="text">0</attribute>
-                  </attributes>
-                </child>
               </object>
               <packing>
                 <property name="left_attach">1</property>

src/disco.py

@@ -549,10 +549,8 @@ _('Without a connection, you can not browse available services'))
             self.address_comboboxentry_entry = self.address_comboboxentry.child
             self.address_comboboxentry_entry.set_activates_default(True)
 
-            liststore = gtk.ListStore(str)
-            self.address_comboboxentry.set_model(liststore)
             self.latest_addresses = gajim.config.get(
-                    'latest_disco_addresses').split()
+                'latest_disco_addresses').split()
             if jid in self.latest_addresses:
                 self.latest_addresses.remove(jid)
             self.latest_addresses.insert(0, jid)