Unable to quit program when using PowerShell

[ScottyMaher]

I know this isn't specifically related to vpython jupyter, but I'm not sure where else to put it. If there is a better place for this query let me know.

As per the documentation at https://vpython.org/presentation2018/install.html
I include from vpython.no_notebook import stop_server and stop_server() at the end of my program, however when it finishes the browser window stays active and I am unable to do anything within PowerShell. Exiting the browser window does not stop the program either. The only way I've found to stop the program from running and regain control is to press ctrl+break, but I'd like for there to be a clean way to do this.

Thanks.