Did you posted in https://lemmy.world/c/[email protected] and https://lemmy.world/c/linux_gaming ? As it is a native linux mode, if I understood correctly, you could post there too. And in gamedev communities too.
What kind of crash ? I had freeze + steam deck reboot a lot, and it continued when I played an old video game, so I looked online and found it was a graphic bug. I fixed it by doing this : https://www.reddit.com/r/SteamDeck/comments/ywc7jb/troubleshooting_guide_for_all_users/
Thanks, I ended in the parameters and found the repositories, but not how to update them.