When configured "Set time limit for disconnected sessions" and "Set time limit for active but idle Remote Desktop Service sessions", the idle timer expired pop-up window always displayed in ICA session in Windows 10.
Both "Set time limit for disconnected sessions" and "Set time limit for active but idle Remote Desktop Service sessions" policies are working in RDP session and Windows Server VDA, that's because ICA session is connected through Windows Terminal Service in Windows Server VDA. but it does not work in Windows 10 single session.
ICA session in Windows 10/11 single session, enable "Session idle timer" and configure "Session idle timer interval" policies.
When configured "Set time limit for disconnected sessions" and "Set time limit for active but idle Remote Desktop Service sessions", the idle timer expired pop-up window always displayed in ICA session in Windows 10.