http://andrewmorgan.ie/2012/07/caffeine-for-citrix-receiver/
Remember this Citrix utility i wrote 8 years ago? no? Me neither, or at least I wouldnt, if you would stop emailing me about it.
In light of COVID-19, constant pestering and peoples desire to avoid work, I've re-written it and i'm putting the whole project up here so you can have it. Or do more with it yourself if you like.
1: .Net Framework 4.7.2
2: Create the following two, DWORD values in the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Citrix\ICA Client\CCM
AllowLiveMonitoring: Dword: 1
AllowSimulationAPI: Dword: 1
3: Download the utility:
4: Run it!
Then go back to doing nothing safe in the knowledge that you shouldnt get a screensaver prompt again!
if you want to tune the keystroke it sends, see the exe.config file if you want to tune the frequency, see the exe.config file.