[Python] PyQt5 QThreads persists in call stack shown by VSCode after thread quitting

I am running this simple SignalManager class to manage running and closing some QThreads spawned by Parent. And this seems to work without a fuss in non-debugging mode. GUI uses around 480 MB and one thread adds roughly 120 MB of RAM and the memory used by the thread is freed once I hit the button responsible for closing the thread.

What I wonder about is why in debugging mode the Dummy-N thread is considered as Running even after closing it. I use latest versions of VSCode (1.97.2) and Microsoft Python Debugger (2025.1.2025022401). Python 3.11.6, PyQt5 version 5.15.10.

class Parent(QMainWindow, SignalManager):
def __init__(self):
super().__init__()
self.signalmanager = SignalManager(self)
# other parent class definitions

class SignalManager:
def __init__(self, parent):
super().__init__()
self.parent = parent

def start_signal_generator(self, channel: int, connector_state: bool):
if channel == 1:
# Ensure the previous thread is properly finished
if hasattr(self, "channel1_thread") and self.channel1_thread is not None:
self.stop_signal_generator(channel)
# Define worker thread
self.channel1_thread = QThread()
self.running_threads.append(self.channel1_thread)
self.channel1_generator = SignalGenerator(self.parent, channel, connector_state)
self.channel1_generator.moveToThread(self.channel1_thread)
self.channel1_thread.started.connect(self.channel1_generator.run)
self.channel1_generator.finished.connect(self.channel1_thread.quit)
self.channel1_generator.finished.connect(self.channel1_generator.deleteLater)
self.channel1_thread.finished.connect(self.channel1_thread.deleteLater)
self.channel1_generator.progress.connect(self._reportProgress)
self.parent.connector1_toggled.connect(lambda state: self.channel1_generator.update_connector_state(state))
self.channel1_thread.start()
else:
logging.debug("Invalid channel number.")

def stop_signal_generator(self, channel):
if channel == 1 and self.channel1_thread is not None and self.channel1_generator.is_running():
self.channel1_generator.stop()
self.channel1_thread.quit()
self.channel1_thread.wait()
self.channel1_thread = None
print("Thread for channel 1 quitted.")
else:
logging.debug("Invalid channel number.")

def _reportProgress(self, channel, t, wfm):
pass

class SignalGenerator(QObject):
finished = pyqtSignal()
progress = pyqtSignal(int, object, object)

def __init__(self, parent, *args, **kwargs):
super().__init__()
self.parent = parent
self.running = True
# Some other class instance definitions

def run(self):
"""Long-running task of generating/updating the signal"""
debugpy.debug_this_thread() # this is for debugging inside `QThread`s (probable culprit of persistent threads in VSCode callstack)

while self.running:
if not self.running:
break
time.sleep(1)
self.progress.emit(1,[1,2,3],[1,2,3])

self.finished.emit()
self.stop()

def stop(self):
self.running = False

def is_running(self):
return self.running


launch.json

{
// Use IntelliSense to learn about possible attributes.
// Hover to view descriptions of existing attributes.
// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
"version": "0.2.0",
"configurations": [
{
"name": "Python Debugger: Current File in Current Workspace with Qt",
"type": "debugpy",
"request": "launch",
"program": "${workspaceFolder}/__main__.py",
"console": "integratedTerminal",
"cwd": "${workspaceFolder}",
"justMyCode": false
}
}

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