Note: This article only applies to Windows and Mac computers running VNC Viewer.
Mac Viewer only: You need to disable "Displays have separate Spaces" in System Preferences, Mission Control.
VNC Viewer can be configured to fill all your local screens with the remote desktop.
To do so, first connect to VNC Server:
Next, click the Properties button on the VNC Viewer toolbar:
Select the Expert tab:
UseAllMonitors into the Filter, and set the Value to True:
Click OK. Click the Enter full screen button on the VNC Viewer toolbar:
VNC Viewer will now fill all your screens. To exit full screen mode, click the Exit full screen toolbar button again.