Computer Configuration > Administrative Templates > Citrix Components > Citrix Workspace > Client Engine
Machine
HKLM\Software\Policies\Citrix\ICA Client\DesktopViewer
If "Disabled" or "Not configured", in-session reconnect will not show reconnection notification after a failed ACR attempt and consequently will not attempt to reconnect session. If "Enabled", in-session reconnect notification will show on failed ACR attempt providing the user a method to get back into their session quickly.