I just got my OLED and wanted to try out HDR on Elden Ring, but the option is greyed out, even in full screen. I tried out Doom Eternal and the HDR turns on and works properly so it seems the problem is limited to Elden Ring.
I saw someone else on here had the same problem but didn’t find a fix so I wanted to see if anyone found a solution for this yet?
I had this same issue. Fixed by changing from borderless window to full screen in Elden Ring settings.