Why can’t I disconnect my only physical display while a virtual screen is connected?

BetterDisplay normally keeps an eligible physical display connected so you are not left without a visible desktop. A BetterDisplay virtual screen does not count as that fallback, even when you can view it through a remote-access app.

A physical monitor connected through DisplayLink is different from a BetterDisplay virtual screen. The safeguard can count a display registered with BetterDisplay’s DisplayLink controller, even though macOS classifies that connection as system virtual. Other system-virtual displays do not count as that fallback. A temporary Generic Display stand-in also does not prevent the app’s automatic recovery from reconnecting a usable screen. If the built-in screen immediately reconnects, check which displays are actually connected and recognized before disabling the safeguard.

For an intentional virtual-screen-only setup, first connect the virtual screen and confirm that your remote-access app can display and control it. Then open Settings > Displays > Overview > Display Connections > Connection Management Settings… and enable Allow disconnecting all connected displays. Connection management requires Pro and a supported display.

With that override enabled, Auto-connect all displays when no connected displays left is inactive, even if its saved preference is on. You do not need to change both switches to defeat the same safeguard. Startup, quit and other reconnection options remain separate. Review them if the monitor returns when you did not expect it to.

Use the physical display's connection switch in BetterDisplay to disconnect it. Making the virtual screen the main display only changes its role. It does not disconnect the physical screen or override the remote client's choice of what to show.

Reconnect the physical screen when returning to local use, and turn off Allow disconnecting all connected displays when you no longer need a virtual-only session. See Display Connections for recovery behavior and sharing a virtual screen for the separate screen-sharing setup.