Good idea. With the live USB my ethernet works fine right from the start. So, it’s not hardware or windows. The one difference I see between the live USB and my current setup is that in the live USB session sudo systemctl status NetworkManager.service returns also the line below which is missing when I execute the command in my actual setup:
audit: op="statistics" interface="enx0050b6cOf7f3" if index=3 args="2000" pid= 1957 uid=1000 result="success"
But Info Center in KDE Plasma lists “enx0050b6cOf7f3” as in my original post.
So, ethernet hardware functions, it works as expected with live USB and Windows. In the debian setup it is detected with an inet address, but NetworkManager ignores it.
DHCP also works – my wifi connection in this debian setup works, as do several devices connected to wifi and ethernet.
Interesting. Just tested, and my ethernet works in a live USB session, so it doesn’t look like it is locked by Windows. Also, I have been properly shutting down, only logging into debian for a couple of weeks but the problem persists.