@@ -2092,7 +2092,8 @@ class DotWindow(Gtk.Window):

             self.error_dialog(str(ex))

     def on_open(self, action):

-        chooser = Gtk.FileChooserDialog(title="Open dot File",

+        chooser = Gtk.FileChooserDialog(parent=self,

+                                        title="Open dot File",

                                         action=Gtk.FileChooserAction.OPEN,

                                         buttons=(Gtk.STOCK_CANCEL,

                                                  Gtk.ResponseType.CANCEL,

@@ -2120,7 +2121,8 @@ class DotWindow(Gtk.Window):

         self.dotwidget.reload()

     def error_dialog(self, message):

-        dlg = Gtk.MessageDialog(type=Gtk.MessageType.ERROR,

+        dlg = Gtk.MessageDialog(parent=self,

+                                type=Gtk.MessageType.ERROR,

                                 message_format=message,

                                 buttons=Gtk.ButtonsType.OK)

         dlg.set_title(self.base_title)