Monitor reports no signal after being turned off and on again when any fullscreen application (Wayland or XWayland) is in focus. Hitting the super key to bring up the application launcher brings back picture and switching focus to a window with a border is also fine. Switching focus back to a fullscreen application gives no signal to the monitor again.
Restarting the desktop solves this until the monitor is restarted.
This problem only occurs when VRR is enabled in KDE Plasma settings. I have reported the issue with the KDE devs who recommended reporting it here too.
555.58.02 driver with an Ampere card.
This is common for me as my OLED monitor needs to do a pixel refresh every so often which involves turning it off and on again.