When I run Heroic (or any game installed with it) the performance overlay for Steam Deck at the top of the screen will flash a few times and then completely go away until I reboot.
I've tried completely uninstalling and reinstalling Heroic with no change. The performance overlay works as expected using: 1) Any native steam game; 2) Any non-steam application that I have added (other than Heroic Launcher); 3) Any game that I have installed via the Junk Store add in.