Threads creation optimization

hopper/countdown_timer.py

@@ -10,11 +10,11 @@ class CountdownTimer(Thread):
         self.seconds = seconds
         self.stop_event = Event()
         self.callback = callback
-        super().__init__()
+        super().__init__(daemon=True)
 
     def run(self) -> None:
         cnt = self.seconds
-        while cnt > 0 and not self.stop_event.is_set():
+        while cnt and not self.stop_event.is_set():
             cnt -= 1
             time.sleep(1)