Hi Giovanni
I tried to reproduce the behavior on the r3.1.1. Whether or not I continue to run the ping -t command on command prompt, when I minimized the RDP screen, the session recording shows the blue screen without appearing anything. After reopen the RDP screen, the session recording shows the situation on the RDP screen.
What you mentioned is about this behavior? If so, I feel that it is a design but I recommend to raise the same question to PAM Expert Forum side also as you are CA employee. Our colleague who is the session recording expert may reply you about it there
Best regards, Kosei