Qmodbus doesn't detect plugging in a new serial port after starting

[cedric-airsupplies]

After qmodbus has been started, Qmodbus doesn't fully detect a new serial port. It does detect there's a serial port, but it cannot be choosen from the serial port drop down menu.

Steps to reproduce:
0) Unplug all USB to serial ports dongles, so the PC doesn't have serial ports anymore.

1. Start qmodbus. this yields the message "Could not find any serial port on this computer." This is correct
2. Click ok. Now the main user interface of Qmodbus comes up.
3. Connect an USB to serial converter to the PC
4. Click on the arrow for the drop down menu of serial port. his list stays empty.

My versions:
QModBus 0.2.1
Windows 10 Home 21H2 19044.3086