Disclaimer: this information was submitted by an affected user and is provided "AS IS" with no warranties. The following steps were not verified or tested by us.
Apply the GPO setting “Best Performance” option to the XenApp servers (this is done per user and cannot be set at the build level):
Change the visual effects on a per user basis to Adjust for best performance. This was applied to the Citrix Application server by GPO
User Configuration Preferences Windows Settings Registry VisualFXSetting (Order: 1)General Action Update Properties Hive HKEY_CURRENT_USER Key path SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\VisualEffects Value name VisualFXSetting Value type REG_DWORD Value data and: User Configuration Administrative Templates Control Panel/Personalization Policy Setting Comment Load a specific theme Enabled Path to theme file: %Systemroot%\Resources\Ease of Access Themes\basic.theme 0x2 (2)