Basically what you have, though I am using bazzite-steam versus steam. Though to be honest I am drawing a blank what the difference is.
No idea what enc is, I don’t have it on my path either. But it sounds like it still launches afterwards, if I am reading you right, so it may be red herring.
You may get more eyes on this in it’s own thread, as it seems like you are hitting a distinct error situation.
Games I’ve confirmed HDR on for reference:
Silent Hill 2
Hunt Showdown
Lies Of P
I really haven’t gone much deeper then that because I can’t only really play gamepad games due to mouse being completely messed up under gamescope.
Since Bazzite 42 is out I am going to close this thread since the world has really changed around HDR support and with Gnome directly supporting HDR this thread feels outdated.
For posterity this is the command I ended up for running on the tty: