At the Citrix Server following policies must be set:
Use video codec for compression must be enabled.
For the entire screen: Text tracking should be enabled if bandwidth is not a problem to increase readability in Office applications
For actively changing regions: Citrix Receiver 13.6+ required, otherwise JPEG fallback will be loaded
Use video codec when preferred: If For actively changing regions is selected by Citrix, a Citrix receiver 13.6+ must be activated, otherwise JPEG fallback is loaded.