diff --git a/IPython/html/widgets/widget.py b/IPython/html/widgets/widget.py
index 1739bd04a..fd0288387 100644
--- a/IPython/html/widgets/widget.py
+++ b/IPython/html/widgets/widget.py
@@ -327,11 +327,11 @@ class Widget(LoggingConfigurable):
# Trigger default traitlet callback machinery. This allows any user
# registered validation to be processed prior to allowing the widget
# machinery to handle the state.
- super(Widget, self)._notify_trait(name, old_value, new_value)
+ LoggingConfigurable._notify_trait(self, name, old_value, new_value)
# Send the state after the user registered callbacks for trait changes
# have all fired (allows for user to validate values).
- if name in self.keys:
+ if self.comm is not None and name in self.keys:
# Make sure this isn't information that the front-end just sent us.
if self._should_send_property(name, new_value):
# Send new state to front-end