diff --git a/IPython/frontend/qt/base_frontend_mixin.py b/IPython/frontend/qt/base_frontend_mixin.py index f59fd50..697d45f 100644 --- a/IPython/frontend/qt/base_frontend_mixin.py +++ b/IPython/frontend/qt/base_frontend_mixin.py @@ -106,4 +106,9 @@ class BaseFrontendMixin(object): from this frontend. """ session = self._kernel_manager.session.session - return msg['parent_header']['session'] == session + parent = msg['parent_header'] + if not parent: + # if the message has no parent, assume it is meant for all frontends + return True + else: + return parent.get('session') == session