You can use up to two monitors with remote desktops.
If you are not connected to a remote desktop, click the Settings toolbar button in the upper-right corner of the desktop and application selector window and turn on the Use Multi Monitors if there are two monitors option in the Settings window. If you have two monitors and you connect to a remote desktop, the multiple-monitor feature is used. If you have only a single monitor, or more than two monitors, single-monitor mode is used. If you switch to another remote desktop, it opens in multiple-monitor mode and the previous remote desktop reverts back to single-monitor mode.
If you are already connected to a remote desktop, you can enable the multiple-monitor feature by turning on the Use Multi Monitors if there are two monitors option in the Settings window, which is available from the sidebar.
The multiple-monitor feature has the following limitations.
It is not supported for published applications.
It is disabled when the client device is working in kiosk mode.
It is not supported if Unified Desktop mode is enabled for the client device.
For information about how to disable kiosk mode or Unified Desktop mode, see the Google Chrome documentation.