=== modified file 'breezy/bzr/smart/server.py'
--- old/breezy/bzr/smart/server.py	2020-06-10 23:47:24 +0000
+++ new/breezy/bzr/smart/server.py	2022-04-12 19:32:07 +0000
@@ -277,19 +277,17 @@
         thread_name = 'smart-server-child' + thread_name_suffix
         handler = self._make_handler(conn)
         connection_thread = threading.Thread(
-            None, handler.serve, name=thread_name)
+            None, handler.serve, name=thread_name, daemon=True)
         self._active_connections.append((handler, connection_thread))
-        connection_thread.setDaemon(True)
         connection_thread.start()
         return connection_thread
 
     def start_background_thread(self, thread_name_suffix=''):
         self._started.clear()
-        self._server_thread = threading.Thread(None,
-                                               self.serve, args=(
-                                                   thread_name_suffix,),
-                                               name='server-' + self.get_url())
-        self._server_thread.setDaemon(True)
+        self._server_thread = threading.Thread(
+            None, self.serve, args=(thread_name_suffix,),
+            name='server-' + self.get_url(),
+            daemon=True)
         self._server_thread.start()
         self._started.wait()
 

