As we haven't done anything special for WS2019 yet, this is a change in Windows (or whatever tool is outputting the text). You could report it to Microsoft. I don't know the best way to report bugs in Windows Server though, but most people with it have support contacts.
The tool is outputing exactly the same file on both WS2019 and WS2016. I guess Popen is using some OS library or environment that has changed in WS2019.
> I guess Popen is using some OS library or environment that has changed in WS2019. Yep, which is why the report should go to those responsible for WS2019. If they say it's an intentional change and users are supposed to work around it themselves, then we can do a workaround, but if it's unintentional then they should fix it.