Anydesk does not display unless the remote host connects to a monitor

I use Anydesk to connect to a remote host (windows 10 + RTX3080), but Anydesk does not show any image unless the remote host is physically connected to a monitor. Anydesk shows that the connection is established but it's waiting for image. It seems that unless the GPU of the remote host is connected to a monitor, it wouldn't send any video signals.

Any solutions? I'd perfer not to use a monitor.

Know someone who can answer? Share a link to this question via email, Twitter, or Facebook.