The below is additional reference information
Configuring the RX-HDX to support the Secondary Display adapter is relatively simple. Below are the necessary steps.
Both Displays must be the same resolution
** In the packaging for the Secondary Display Adapter (SDA) there are TWO USB cables. Using one cable from a USB port on the Primary RX-HDX to the USB Micro port labeled USB on the SDA in most cases will be sufficient. if a single USB cable is used be sure NOT to connect to the "power" port on the SDA
1. On the device and in No Touch Center NTC - DO NOT CHANGE THE DISPLAY SETTINGS FOR MULTIMONITOR MODE, Leave these settings as default. It may seem natural to want to change these settings, but they only effect the local X11 Window manager and may have a negative effect for Dual Display in a Citrix Environment
2. H.264 Settings on the device
H.264 support must be enabled for the
Citrix connection where Secondary Display Adapter will be used
-The ‘no setting’ selection will be used by default for all newly
created Citrix connections
-This is OK, as Citrix Receiver will respect Citrix server’s preference
3. On the RX-HDX device you should ensure that you have a minimum Firmware image level of 2.40.2443-NC-k404-armhf-171219
4. Citrix settings - The target VDA \ VDI must have the Policy setting
•Citrix server (the VDA machine)
must use the H.264 encoder for the entire session screen
-In XenApp/XenDesktop up to version 7.6 the H.264 (aka deep compression)
was the default display mode
-From version 7.6 FP3 the display mode is configurable through Citrix
Policy
-‘Use video codec for compression’ : ‘For the entire screen’ is the
right selection
-On older system selecting the ‘Use when available’ option may be
necessary
** it is important to note that the Secondary display will show the Citrix logo until after a session has been established. This is expected behavior **