GE has reorganized the gamescope packages to be more usable for those on desktops that just want the option to use gamescope-session (Steam Deck mode):
1. Run your system updater or manually update these packages:
nobara-updater
gamescope-session-plus
gamescope-session-steam
gamescope-htpc-common (it will pull in a new dependency -- gamescope-session-common)
2. If you do NOT want the streamlined htpc mode (which includes SteamOS logo, plymouth image, no grub menu, no grub timeout, and auto-updater inside the session): after updating the above packages, remove gamescope-htpc-common, then run the quirks from the updater (nobara-sync).
gamescope-session-plus
gamescope-session-steam
gamescope-session-common
gamescope-session-plus
gamescope-session-steam
gamescope-session-common
gamescope-htpc-common
gamescope-session-plus
gamescope-session-steam
gamescope-session-common
gamescope-htpc-common
gamescope-handheld-common
jupiter-hw-support
jupiter-fan-control
Run quirks from updater (
nobara-sync) after installing/removing which packages you want.
After installing gamescope session, you can make it default option in the plasma session manager (for KDE).
Keep in mind that gamescope session support for Nvidia GPUs is much less stable than on AMD GPUs.