diff --git a/omemo/gtk/config.py b/omemo/gtk/config.py
index fb7f6ca..ca61071 100644
--- a/omemo/gtk/config.py
+++ b/omemo/gtk/config.py
@@ -77,7 +77,7 @@ class OMEMOConfigDialog(GajimPluginConfigDialog):
     def update_account_combobox(self):
         if self.plugin_active is False:
             return
-        if self._ui.account_store:
+        if len(self._ui.account_store):
             self._ui.account_combobox.set_active(0)
         else:
             self.account_combobox_changed_cb(self._ui.account_combobox)
@@ -130,7 +130,7 @@ class OMEMOConfigDialog(GajimPluginConfigDialog):
     def update_context_list(self):
         self._ui.deviceid_store.clear()
 
-        if not self._ui.account_store:
+        if not len(self._ui.account_store):
             self._ui.ID.set_markup('')
             self._ui.fingerprint_label.set_markup('')
             self._ui.refresh.set_sensitive(False)
diff --git a/omemo/gtk/config.ui b/omemo/gtk/config.ui
index d80a188..05e88f0 100644
--- a/omemo/gtk/config.ui
+++ b/omemo/gtk/config.ui
@@ -270,6 +270,7 @@
               <object class="GtkButton" id="cleardevice_button">
                 <property name="label" translatable="yes">_Clear Devices</property>
                 <property name="visible">True</property>
+                <property name="sensitive">False</property>
                 <property name="can_focus">True</property>
                 <property name="receives_default">True</property>
                 <property name="tooltip_text" translatable="yes">This clears your device list from the server.
@@ -292,6 +293,7 @@ It is advised to go online with all of your actively used devices after clearing
                 <property name="label">gtk-refresh</property>
                 <property name="width_request">160</property>
                 <property name="visible">True</property>
+                <property name="sensitive">False</property>
                 <property name="can_focus">True</property>
                 <property name="receives_default">True</property>
                 <property name="use_stock">True</property>