diff --git a/Orange/widgets/visualize/utils/__init__.py b/Orange/widgets/visualize/utils/__init__.py
index d152de9bf2d..f4c714d4f93 100644
--- a/Orange/widgets/visualize/utils/__init__.py
+++ b/Orange/widgets/visualize/utils/__init__.py
@@ -86,7 +86,7 @@ class Information(WidgetMessagesMixin.Information):
 
     def __init__(self, master):
         """Initialize the attributes and set up the interface"""
-        QDialog.__init__(self, windowTitle=self.captionTitle)
+        QDialog.__init__(self, master, windowTitle=self.captionTitle)
         WidgetMessagesMixin.__init__(self)
         self.setLayout(QVBoxLayout())
 
@@ -182,6 +182,10 @@ def hideEvent(event):
 
         def deleteEvent():
             vizrank.keep_running = False
+            if vizrank._thread is not None and vizrank._thread.isRunning():
+                vizrank._thread.quit()
+                vizrank._thread.wait()
+
             master_delete_event()
 
         master.closeEvent = closeEvent