In order to utilize multiple monitors with a Citrix VDI desktop, follow these steps:
Launch the Citrix remote Desktop
Position the VDI Desktop so 1/2 of the screen is on each of the 2 available monitors
Locate and extend the toolbar tab from the top of the screen in the remote desktop session.
Extend the black tab from the top of the screen in the remote desktop session and click “Full Screen”
You can now drag the contents across two monitors. Have a wonderful remote working.