I’m using PyQT6 on MacOS and exec() to open dialog

if dialog.exec() == QDialog.DialogCode.Accepted:
    print("Adding...")
else:
    print("Adding cancelled")

The reason for exec is to block the execution until I get result from the dialog. However, often I am getting the following lines

TSMSendMessageToUIServer: CFMessagePortSendRequest FAILED(-1) to send
to port com.apple.tsm.uiserver

What this error means and how to solve it?