Thanks for the URL. I followed the instructions and manipulated various choices for foreground text color, but none of my choices made the CoPilot "You" dialog text visible. It's not clear to me what color parameter(s) control the foreground color of the You font displayed.
I use the Win 11 "Night Sky" contrast theme on my Desktop computer. When I type a text question into the CoPilot "Ask me anything..." box it repeats my text in a "You" box (and then addresses my question in a "CoPilot" box). The text shown in the "You" box is almost unreadable as it is...