Warning "You are currently using the RemoteFX 3D Video Adapter"

I also kept receiving that popup. I do not have any VM running but I do have WSL2 running, which it does on top of Hyper-V (plus Docker using WSL2, I do not know if this plays a role in it).

Here is what I did :

  1. Get the name of the video card. Here I could see that the driver was enabled.

enter image description here

  1. Disable RemoteFX adapter. Obviously, provide it with the name of your own card.
Disable-VMRemoteFXPhysicalVideoAdapter -Name "NVIDIA Geforce GTX 970"

Now I cannot really check if this worked because the popup only appears very not-often, but it does show disabled :

enter image description here

After reading @Mickael's answer, this worked for me (at an Admin Powershell prompt):

Get-VMRemoteFXPhysicalVideoAdapter | ?{$_.Enabled} | Disable-VMRemoteFXPhysicalVideoAdapter