I did this many years ago with a dual boot computer and Windows (7 iirc) kept complaining about needing to be reactivated when I’d switch between running natively and virtualized. Has that been fixed on Windows 10?
If you substantially change the hardware of your computer, you are supposed to get a new licence because it's like it is another computer. It's not a bug but a feature.
In my case, the first time I fully booted the Windows 10 disk was in the VM. I wonder if this counted as a 'change' or does it think that the VM is the original hardware now?
What most people want is to pay and then not worry about random downgrades and deactivations, even if they upgrade a parr or two, or boot the same machine indirectly through a hyper visor.
Apparently, Microsoft does not or cannot deliver this, and as we’ve seen this week may randomly downgrade your system even if nothing changed.